Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Fri Jun 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM OHIO INTO PORTIONS WEST VIRGINIA...MARYLAND...PENNSYLVANIA AND NEW YORK... ...SUMMARY... Scattered damaging winds and a couple tornadoes are possible on Saturday from parts of Ohio into northern West Virginia/Maryland, central and western Pennsylvania, and western New York. ...Ohio Valley to the Northeast... Several vorticity maxima are forecast to migrate across the region within an area of enhanced southwesterly flow aloft ahead of the main upper shortwave trough progressing from the Upper Midwest to the lower Great Lakes. At the surface, low pressure will spread east/northeast from the upper Great Lakes into Ontario/Quebec. As this occurs, strong theta-e advection on southwesterly low-level flow will result in a very moist airmass spreading north/northeast from the Midwest into much of the Northeast. Early cloudiness and periods of showers may limit diurnal destabilization from eastern PA into NY. Pockets of stronger instability will overlap 30-40 kt westerly midlevel flow from parts of Ohio into western/central PA/NY. While midlevel lapse rates will remain quite poor, sufficient effective shear magnitudes amid rich boundary-layer moisture should support organized clusters and line segments capable of strong/damaging gusts. Vertically veering low-level winds will support somewhat enlarged and curved hodographs, with sufficient low-level instability and 0-1 km SRH. In addition to damaging gusts, a couple of tornadoes also will be possible. A more conditional risk may exist from late evening into the early overnight hours across parts of northern NY into VT as the surface front impinges on the area and the main upper shortwave trough ejects eastward. Strong vertical shear will be in place amid a very moist airmass. However, convection may remain elevated given poor timing with the diurnal cycle and impacts from daytime convection. If convection can become surface-based, damaging gusts will be possible. ...OK/KS to the Mid-MS Valley... Convection may be ongoing Saturday morning across parts of central MO. This activity may weaken during the morning, or slowly reintensify during the afternoon along outflow or the southward-advancing surface cold front. Additional convection is expected to develop along the sagging front across southern KS/northern OK during the late afternoon/evening. A couple of forward-propagating clusters are possible within this area of modest vertical shear, but rich boundary-layer moisture (dewpoints in the upper 60s/low 70s F) and moderate to strong instability. Isolated severe/damaging gusts and a few instances of hail will be possible with this activity. A corridor of higher probabilities may be needed in subsequent outlooks if confidence increases in location of better organized frontal convection. ...Central/Southern High Plains... Isolated convection is expected during the evening in a post-frontal upslope flow regime. Near 60 F surface dewpoints and steep midlevel lapse rates will support a corridor of moderate instability. While deep-layer flow will be light, vertically veering wind profiles will support 30-40 kt effective shear magnitudes amid a deeply mixed boundary-layer. Isolated strong to severe thunderstorms capable of strong gusts and hail will be possible. ...Northern IL into eastern WI and MI... Most forecast guidance is fairly sparse with convection across this area on Saturday. However, a very moist and unstable airmass will be in place ahead of the east/southeast-advancing cold front, along with favorable vertical shear for organized storms. Large-scale ascent will remain somewhat weak and ill-timed with the cold front progression, and low-level frontal convergence also will be poor. Severe probabilities have been adjusted some over the region based on low storm coverage and latest trends. However, a conditional severe threat will exist if storms develop. ..Leitman.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Jun 28 2024 Valid 281630Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE MID MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging winds, and a couple of tornadoes may occur from parts of the central Plains into the mid/upper Mississippi Valley this afternoon and tonight. ...Synopsis... An upper low over the northern Rockies/High Plains will progress eastward today to the Upper Midwest. At the surface, an occluded low is forecast to meander slowly eastward over northern MN through this evening, while a secondary low consolidates over central KS. An occluded/cold front extending from the northern MN low will develop slowly southeastward across the central Plains and mid MO Valley this afternoon. This boundary will likely serve as a focus for strong/severe convection later today. ...Central Plains into the Mid Mississippi Valley... Better forcing for ascent associated with the upper trough/low should generally remain displaced to the north of the central Plains and mid MO Valley through much of the day. Also, the lingering effect of morning clouds/precipitation will be to slow diurnal destabilization to some extent. Still, low-level convergence along the cold front and glancing large-scale ascent will probably be sufficient for convective initiation through 20-00Z across parts of IA into eastern NE, and northeast KS into northern MO. Even modest daytime heating of the moist low-level airmass ahead of the front will support a narrow corridor of moderate to locally strong instability. Strengthening westerly winds through mid/upper levels will foster strong deep-layer shear and updraft organization. Initial development along the cold front from eastern NE into central IA may be supercellular, with an associated threat for large hail. Upscale growth into clusters and short line segments with a greater severe/damaging wind threat seems probable with time this evening. The eastern extent of the severe risk across the mid MS Valley will be modulated by the narrow zone of stronger instability, and convection should gradually weaken as it continues eastward late this evening and overnight. The tornado threat across these areas today appears less clear. While a modest southwesterly low-level jet will aid in sufficient low-level shear for updraft rotation, it remains unclear whether multiple supercells will be able to persist into the early evening hours. Still, some threat for a couple tornadoes remains apparent, mainly near/northeast of the surface low in northeast KS and vicinity where low-level shear should be locally maximized. A separate area of high-based convective development should occur this afternoon across the central High Plains, along/north of the cold front in a weak low-level upslope flow regime. This activity will move generally east-southeastward through the evening through a very well-mixed boundary layer, with generally weak to moderate instability present. Although low-level winds should remain modest, gradually increasing westerly flow at mid/upper levels should support sufficient deep-layer shear for convective organization. Severe/damaging winds appear to be the main threat as one or more small clusters continue east-southeastward across western/central NE/KS late this afternoon and evening. Isolated gusts of 75+ mph may occur if convection can become well organized into a small bowing cluster. Some large hail also appears possible, particularly with any initial supercells. ...Northern Plains into the Upper Mississippi Valley... Isolated to scattered thunderstorms should develop along an occluded front extending into parts of ND as the upper trough/low moves eastward over the northern Plains today. While instability appears fairly modest, occasional hail and strong/gusty winds may occur with the more robust convection given the presence of sufficient deep-layer shear. ..Gleason/Thornton.. 06/28/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CDT Fri Jun 28 2024 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... Locally elevated conditions are likely in portions of southeast California into southern Nevada that overlap with the current Fuels and Fire Behavior Advisory for well above normal fine fuel loading. Otherwise, the previous forecast remains on track. ..Nauslar.. 06/28/2024 .PREV DISCUSSION... /ISSUED 0125 AM CDT Fri Jun 28 2024/ ...Synopsis... A mid-level trough will eject into the Northern Plains today as upper ridging builds over the Interior West. A surface cold front trailing the mid-level trough will sweep southward across the northern High Plains while monsoonal mid-level moisture meanders over the central Rockies into parts of the Desert Southwest. While elevated to critically dry and windy conditions will accompany the cold front across portions of southern Wyoming, fuels are too poorly receptive to support significant wildfire-spread potential. The thunderstorms supported by monsoonal moisture across the central Rockies into the Southwest should also be relatively slow moving, wet, and will traverse areas that have received rainfall in previous days. As such, lightning should occur over relatively moist fuels, limiting wildfire ignitions to a degree. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Fri Jun 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE CENTRAL PLAINS INTO PARTS OF THE MIDDLE AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Large hail, damaging wind and a few tornadoes will be possible from parts of the central Plains into parts of the Middle and Upper Mississippi Valley today and tonight. ...Synopsis... The main mid/upper-level perturbation influencing convective potential this period is a strong shortwave trough accompanying a small cyclone now centered over southwestern SK. The cyclone is expected to open up today, with a 00Z trough position from southwestern MB southwestward across northern/western ND to northeastern WY. The trough should accelerate eastward across the remainder of the Dakotas and MN overnight, reaching WI and Lake Superior by 12Z tomorrow. This will occur as a closely following shortwave digs southeastward across southern MB toward northwestern MN. The subtropical ridge will build across the Southeast, southern Plains and into parts of the Desert Southwest. Despite rising absolute height values, this will yield a tightening height gradient across the central Great Plains between the ridge and the northern-stream trough. The 11Z surface analysis showed a low over eastern ND, with cold front extending across eastern SD, central NE, northwestern KS, and east-central CO. A surface trough was drawn from a cold-frontal intersection over central NE south-southwestward to the southern High Plains. The low should cross the Boundary Waters region of the MN/ON border this afternoon through 00Z, when the cold front should extend to southern MN, southeastern NE, through a weak frontal-wave low over central/north-central KS, to southwestern KS, becoming a diffuse warm front over eastern CO. By 12Z, the low should reach that portion of ON northeast of Lake Superior, with cold front to eastern Upper MI, Lake Michigan, southeastern WI, then near a line from DVN-MKC-ICT-DHT. ...Central Plains to Mississippi Valley... This severe-risk area is a composite of two separate potential convective episodes, with the western (second) potentially lasting long enough and far enough east to overlap into the hours-earlier starting region of the first. 1. Lower Missouri Valley, eastern NE/northern KS eastward: An extensive area of clouds and precip, with isolated to widely scattered, embedded, non-severe thunderstorms, was apparent in radar composites and satellite imagery from astern MN and WI across parts of IA, northern/western MO and eastern KS. Although this will delay substantial diurnal heating across much of the mid/upper Mississippi and lower Missouri Valley regions, sufficient destabilization (from diabatic heating and warm advection) is expected by midafternoon to support surface-based development near the cold front. Favorable low-level moisture (dewpoints in the upper 60s to low 70s F) will support a prefrontal plume of MLCAPE in the 2000-3500 J/kg range. Modest low-level flow will limit ambient hodograph size, but sufficient deep shear will exist (effective-shear magnitudes 35-45 kt) to support both supercells and organized multicells. Backing of winds along and just north of the front also will enlarge hodographs in a narrow corridor, with vorticity from the boundary potentially ingested into favorably positioned updrafts for locally boosted tornado potential. Development should be most likely and dense near and northeast of the frontal-wave low, south of which low-level lift will weaken amid rising heights aloft, and buoyancy will decrease toward the OK border. As such, probabilities for this lobe of the outlook area have been tightened northward somewhat. Still, upscale coalescence into one or more clusters/lines should occur, with severe wind the greatest threat this evening into tonight, and a tornado or two possible. 2. Central High Plains and eastward: Widely scattered to scattered thunderstorms are expected this afternoon over higher terrain of western/central CO, with additional initiation possible on the foothills, Cheyenne Ridge and Palmer Divide. This convection will be supported by sustained diurnal heating and related weakening of MLCINH, along with moist advection and upslope lift by the easterly component of post-frontal flow. That moist advection also should offset moisture loss from vertical mixing enough to maintain buoyancy, with MLCAPE in the 250-800 J/kg range. A deep subcloud mixed layer with steep lapse rates will encourage strong-severe downdrafts. Though weak, low-level flow will veer with height, leading to long hodographs and contributing to effective-shear magnitudes ranging from around 30 kt in the southwestern part of the outlook (where coverage also is more uncertain but conditional severe potential still apparent) to 45-50 kt over and downshear from the Cheyenne Ridge. As such, a high-based mix of multicells and supercells is possible, offering mainly damaging gusts and large hail (each with some significant severe possible). One or more clusters may evolve and move eastward to southeastward over KS this evening and overnight, with severe gusts the main concern. ..Edwards/Kerr.. 06/28/2024 Read more