Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jun 15 2024 Valid 152000Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS...AND THE MID MISSOURI VALLEY... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening across the Mid-Missouri Valley, and also from eastern Montana to the western/central Dakotas. A few tornadoes could occur in eastern Nebraska and western Iowa, with isolated significant severe hail and wind possible across parts of the northern Plains. ...20Z Update... ...Northern High Plains/Northern Plains... Overall forecast remains on track. One minor change for this update was to bring 5% wind probabilities back farther west across central MT where thunderstorms have recently developed. As mentioned in MCD #1269, a few locally strong gusts may occur as storms continue to develop across central Montana. Otherwise, the forecast reasoning outlined in the previous outlook for this region remains valid. ...Central High Plains... Another minor expansion was made to include more of far northeast CO in 5% wind probabilities. As mentioned in MCD #1268, high-based storm development will continue over the higher terrain, before spreading eastward with time. High-based storm character could promote evaporative cooling in the sub-cloud layer, and a few enhanced gusts capable of producing wind damage will be locally possible across the area into this evening. ...Elsewhere... Thunderstorm development is still anticipated later this afternoon and evening across the Mid MO Valley, where environmental conditions will support strong to severe storms capable of large hail and damaging gusts. A tornado or two is also possible across eastern NE and western IA, where 30 to 35 kt low/mid-level flow is lengthening hodographs. Isolated severe storms are still possible along the lee troughing across the southern High Plains. High cloud bases and a deeply boundary layer will promote the potential for damaging gusts. ..Mosier.. 06/15/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 15 2024/ ...Northern Plains... A pronounced upper trough/low will progress eastward across the northern Rockies/High Plains and western Canada through the period. A related mid-level jet will begin to overspread the northern High Plains later this afternoon. This feature will contribute to strengthening flow aloft and increasing deep-layer shear to support organized severe thunderstorms. At the surface, a low should consolidate by early evening over eastern MT and the western Dakotas, with a cold front forecast to sweep eastward over the northern Plains this evening and overnight. Near and east of the surface low, around 1500-2500 J/kg of MLCAPE should develop through peak heating across parts of the western/central Dakotas, as a modestly moist low-level airmass continues to advect northward. Current expectations are for high-based thunderstorms to initially develop early this afternoon across parts of central MT as large-scale ascent preceding the upper trough overspreads this region. A well-mixed boundary layer combined with sufficient instability should encourage severe downdraft winds with any cluster that can form/persist with eastward extent. Isolated significant severe winds up to around 75 mph appear possible. The Slight Risk has been expanded westward some into more of central MT to account for this scenario. A somewhat separate area of convection may develop across the Bighorns of northern WY, and subsequently spread eastward across western/central SD through this evening with a threat for mainly severe/damaging winds. Any sustained supercells that can develop should pose a threat for large to very large hail given the favorable thermodynamic and kinematic environment present. This appears most probable across parts of western ND this evening, although there is still some uncertainty regarding what the dominant convective mode will be. A tornado or two may also occur across western ND and vicinity with any supercell that persists this evening as 0-1 km SRH gradually increases in tandem with a strengthening low-level jet. ...Mid Missouri Valley/Central Plains... Morning visible satellite and radar imagery show multiple MCVs across the central Plains and Mid MO Valley associated with prior convection. A shortwave trough will move eastward across these regions through the day, with modestly enhanced mid-level winds overspreading parts of NE/IA and vicinity. At the surface, a warm front will attempt to lift slowly northward over this region as well, but outflow from ongoing elevated convection in northern MO may slow its progress to some extent. This outflow boundary may also severe as an effective warm front and thunderstorm initiation zone this afternoon. Regardless, a gradually destabilizing airmass is anticipated across eastern NE through mid/late afternoon as filtered daytime heating occurs. Most guidance continues to suggest that around 2000-3000 J/kg of MLCAPE will develop in a narrow corridor along/near the warm front by 20-21Z, with steep mid-level lapse rates aiding in this development. Although deep-layer shear does not appear overly strong, it should be sufficient for a few supercells to develop initially. In addition to a threat for large hail with these supercells, a few tornadoes may also occur given the presence of a 30-35 kt southerly low-level jet and enhanced low-level SRH in the vicinity of the warm front. Some upscale growth could occur this evening, with a potentially greater severe/damaging wind threat with any small cluster that can persist into IA and perhaps southern MN. ...Southern High Plains... Isolated to scattered thunderstorms are forecast to develop this afternoon through early evening along/east of a weak surface trough/dryline across parts of the southern High Plains, including the OK/TX Panhandles southward to west TX. Weak to moderate instability and modest deep-layer shear should support some convective organization. Isolated severe wind gusts will be possible with a generally hot and well-mixed boundary layer, along with some potential for hail with the more robust cores. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Sat Jun 15 2024 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN UTAH...NORTHERN ARIZONA...AND FAR SOUTHEAST NEVADA... The Critical and Elevated areas across parts of Utah, Arizona, western Colorado, and western New Mexico were expanded in response to a trend in guidance for windier and drier conditions in these locales. Additionally, some brief, localized Elevated conditions are possible across parts of southeast Colorado, given the expectation of RH below 15% and somewhat dry fuels. However, wind speeds at the moment appear rather modest, and therefore no Elevated areas are introduced in this region for this update. Otherwise, see the previous discussion for more details. ..Supinie.. 06/15/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Jun 15 2024/ ...Synopsis... The western US trough will deepen on Sunday, with strengthening southwesterly flow overspreading much of the desert Southwest. Fuels in this region have seen significant drying after several days of warm and dry conditions. Latest guidance indicates ERCs are in the 90th percentile across much of northern and central Arizona. This is further supported by recent fire activity in this region. Relative humidity reductions to 5-10 percent will overlap sustained winds 15-20 mph across central/northern Arizona and southern Utah, where a Critical delineation was included with this outlook. Outside of this region, a more broad area of Elevated fire weather conditions will be possible across much of central/southern Nevada into southern Arizona, where there is less confidence is sustained Critical wind speeds. Elevated conditions may also extend into portions of western Nevada in the lee of the Sierras. In this region, afternoon relative humidity reductions to 15-20 percent will overlap sustained winds 10-15 mph (locally higher) amid modestly receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Sat Jun 15 2024 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN UTAH...NORTHERN ARIZONA...AND FAR SOUTHEAST NEVADA... The Critical and Elevated areas across parts of Utah, Arizona, western Colorado, and western New Mexico were expanded in response to a trend in guidance for windier and drier conditions in these locales. Additionally, some brief, localized Elevated conditions are possible across parts of southeast Colorado, given the expectation of RH below 15% and somewhat dry fuels. However, wind speeds at the moment appear rather modest, and therefore no Elevated areas are introduced in this region for this update. Otherwise, see the previous discussion for more details. ..Supinie.. 06/15/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Jun 15 2024/ ...Synopsis... The western US trough will deepen on Sunday, with strengthening southwesterly flow overspreading much of the desert Southwest. Fuels in this region have seen significant drying after several days of warm and dry conditions. Latest guidance indicates ERCs are in the 90th percentile across much of northern and central Arizona. This is further supported by recent fire activity in this region. Relative humidity reductions to 5-10 percent will overlap sustained winds 15-20 mph across central/northern Arizona and southern Utah, where a Critical delineation was included with this outlook. Outside of this region, a more broad area of Elevated fire weather conditions will be possible across much of central/southern Nevada into southern Arizona, where there is less confidence is sustained Critical wind speeds. Elevated conditions may also extend into portions of western Nevada in the lee of the Sierras. In this region, afternoon relative humidity reductions to 15-20 percent will overlap sustained winds 10-15 mph (locally higher) amid modestly receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Sat Jun 15 2024 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN UTAH...NORTHERN ARIZONA...AND FAR SOUTHEAST NEVADA... The Critical and Elevated areas across parts of Utah, Arizona, western Colorado, and western New Mexico were expanded in response to a trend in guidance for windier and drier conditions in these locales. Additionally, some brief, localized Elevated conditions are possible across parts of southeast Colorado, given the expectation of RH below 15% and somewhat dry fuels. However, wind speeds at the moment appear rather modest, and therefore no Elevated areas are introduced in this region for this update. Otherwise, see the previous discussion for more details. ..Supinie.. 06/15/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Jun 15 2024/ ...Synopsis... The western US trough will deepen on Sunday, with strengthening southwesterly flow overspreading much of the desert Southwest. Fuels in this region have seen significant drying after several days of warm and dry conditions. Latest guidance indicates ERCs are in the 90th percentile across much of northern and central Arizona. This is further supported by recent fire activity in this region. Relative humidity reductions to 5-10 percent will overlap sustained winds 15-20 mph across central/northern Arizona and southern Utah, where a Critical delineation was included with this outlook. Outside of this region, a more broad area of Elevated fire weather conditions will be possible across much of central/southern Nevada into southern Arizona, where there is less confidence is sustained Critical wind speeds. Elevated conditions may also extend into portions of western Nevada in the lee of the Sierras. In this region, afternoon relative humidity reductions to 15-20 percent will overlap sustained winds 10-15 mph (locally higher) amid modestly receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Sat Jun 15 2024 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN UTAH...NORTHERN ARIZONA...AND FAR SOUTHEAST NEVADA... The Critical and Elevated areas across parts of Utah, Arizona, western Colorado, and western New Mexico were expanded in response to a trend in guidance for windier and drier conditions in these locales. Additionally, some brief, localized Elevated conditions are possible across parts of southeast Colorado, given the expectation of RH below 15% and somewhat dry fuels. However, wind speeds at the moment appear rather modest, and therefore no Elevated areas are introduced in this region for this update. Otherwise, see the previous discussion for more details. ..Supinie.. 06/15/2024 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Jun 15 2024/ ...Synopsis... The western US trough will deepen on Sunday, with strengthening southwesterly flow overspreading much of the desert Southwest. Fuels in this region have seen significant drying after several days of warm and dry conditions. Latest guidance indicates ERCs are in the 90th percentile across much of northern and central Arizona. This is further supported by recent fire activity in this region. Relative humidity reductions to 5-10 percent will overlap sustained winds 15-20 mph across central/northern Arizona and southern Utah, where a Critical delineation was included with this outlook. Outside of this region, a more broad area of Elevated fire weather conditions will be possible across much of central/southern Nevada into southern Arizona, where there is less confidence is sustained Critical wind speeds. Elevated conditions may also extend into portions of western Nevada in the lee of the Sierras. In this region, afternoon relative humidity reductions to 15-20 percent will overlap sustained winds 10-15 mph (locally higher) amid modestly receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more