Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1052 AM CDT Fri Jun 21 2024 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND INTO THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. ..Hart/Halbert/Weinman.. 06/21/2024 Read more

No Mesoscale Discussions are in effect as of Fri Jun 21 13:50:02 UTC 2024.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Fri Jun 21 2024 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY AND OVER THE FOUR CORNERS REGION... ...SUMMARY... Scattered strong to severe storms are expected from parts of the northern High Plains into the upper Mississippi Valley, mainly this afternoon and evening. Scattered strong/severe thunderstorms are also possible across the Four Corners vicinity. A few strong storms may occur from parts of the lower Great Lakes to southern New England. ...Northern High Plains... A shortwave trough will shift eastward from the Canadian Rockies toward Saskatchewan, with southeasterly low-level flow deep into Montana ahead of this shortwave trough. Relatively strong (40 kt) mid-level flow will develop across central Montana as the upper ridge flattens. Scattered robust convection should easily develop within a flow regime favorable for supercells. Forecast soundings, especially for central Montana, exhibit favorable deep-layer shear with strong buoyancy and relatively low cloud bases. Scattered supercells should evolve by early afternoon then propagate southeastward along the instability axis toward eastern/south-central Montana through early evening. Very large hail and gusty winds are expected along with some tornado risk. ...Middle Missouri Valley/Siouxland to Upper Mississippi Valley... Scattered thunderstorms persist this morning regionally in vicinity of the convectively modified frontal zone. A mid-level impulse over Colorado/southeast Wyoming this morning will reach the Siouxland by late afternoon and early evening, all while a south-southwesterly low-level jet markedly intensifies after sunset. Strong diurnal heating south of the boundary will ease CINH across the warm sector and scattered storms are expected to develop and intensify. Updrafts may initially develop along the cool side of the boundary but with time surface-based storms are expected. Hail, wind, and perhaps a couple tornadoes can be expected with supercells occurring near the front. ...Four Corners Region... A seasonally high PW plume will advance into the Four Corners region as a low-latitude shortwave trough over southern California/Nevada ejects over the Great Basin, strengthening mid-level flow across southern Utah into southwestern Colorado. Sustained multicells and some supercells should develop along the southern fringe of this shortwave trough, where strong shear will support organized longer-lived updrafts. Large hail and strong/gusty winds can be expected, and some tornado risk may exist as well. ...Lower Great Lakes to southern New England... Strong boundary-layer heating will once again occur across the lower Great Lakes region into portions of southern New England, with a southward-shifting front focusing scattered convection into early/mid-afternoon. Within a moderately unstable environment, localized wind damage will be the primary concern with the strongest storms his afternoon through around sunset. ..Guyer/Mosier.. 06/21/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0346 AM CDT Fri Jun 21 2024 Valid 241200Z - 291200Z ...DISCUSSION... ...D4/Monday: Northern Plains into the upper MS Valley/Great Lakes... A mid/upper-level shortwave trough and deepening surface low are forecast to move across parts of SK/MB on Monday. A surface trough will extend southward from the low into the northern Great Plains, with secondary surface low development possible across the Dakotas. A warm front will move northeastward somewhere from the eastern Dakotas into the upper MS Valley. Strong buoyancy is forecast to develop near and to the south/west of the warm front, with favorable deep-layer shear providing a conditionally favorable environment for severe thunderstorms. While some severe potential appears likely to evolve somewhere from the northern Plains into the upper MS Valley and/or upper Great Lakes, guidance varies regarding the position of the warm front, and also the southern extent of height falls and large-scale ascent attendant to the SK/MB shortwave trough. Much of the warm sector will likely remain capped, but severe storm development will be possible in closer proximity to the warm front and secondary surface low, which could potentially grow upscale and move southeastward along the instability gradient. Severe probabilities will likely be needed once confidence increases regarding the placement of the primary surface features. ...D5/Tuesday: Upper Midwest into the central/southern Plains... The shortwave trough that moves across parts of SK/MB on Monday is generally forecast to move east-southeastward on Tuesday across parts of ON and the upper Great Lakes. Model spread regarding the timing and track of this shortwave continues to increase at this time range, and the potential for MCS development on D4/Monday further reduces predictability regarding the severe threat on Tuesday. However, some severe-thunderstorm potential may evolve along a southeastward moving cold front from the Great Lakes/upper Midwest into parts of the central/southern Great Plains. ...D6/Wednesday - D8/Friday... Some threat for strong to severe thunderstorms could continue to accompany a southeastward-moving cold front on D6/Wednesday from the southern Plains into the Ohio Valley and Northeast, though predictability remains low regarding the details at this time range. By D7/Thursday into D8/Friday, extended-range guidance generally suggests the potential for a mid/upper-level shortwave trough to move across the northern Rockies toward the northern High Plains. However, model spread remains rather high regarding the evolution of moisture return and any increasing severe potential in association with this system. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0346 AM CDT Fri Jun 21 2024 Valid 241200Z - 291200Z ...DISCUSSION... ...D4/Monday: Northern Plains into the upper MS Valley/Great Lakes... A mid/upper-level shortwave trough and deepening surface low are forecast to move across parts of SK/MB on Monday. A surface trough will extend southward from the low into the northern Great Plains, with secondary surface low development possible across the Dakotas. A warm front will move northeastward somewhere from the eastern Dakotas into the upper MS Valley. Strong buoyancy is forecast to develop near and to the south/west of the warm front, with favorable deep-layer shear providing a conditionally favorable environment for severe thunderstorms. While some severe potential appears likely to evolve somewhere from the northern Plains into the upper MS Valley and/or upper Great Lakes, guidance varies regarding the position of the warm front, and also the southern extent of height falls and large-scale ascent attendant to the SK/MB shortwave trough. Much of the warm sector will likely remain capped, but severe storm development will be possible in closer proximity to the warm front and secondary surface low, which could potentially grow upscale and move southeastward along the instability gradient. Severe probabilities will likely be needed once confidence increases regarding the placement of the primary surface features. ...D5/Tuesday: Upper Midwest into the central/southern Plains... The shortwave trough that moves across parts of SK/MB on Monday is generally forecast to move east-southeastward on Tuesday across parts of ON and the upper Great Lakes. Model spread regarding the timing and track of this shortwave continues to increase at this time range, and the potential for MCS development on D4/Monday further reduces predictability regarding the severe threat on Tuesday. However, some severe-thunderstorm potential may evolve along a southeastward moving cold front from the Great Lakes/upper Midwest into parts of the central/southern Great Plains. ...D6/Wednesday - D8/Friday... Some threat for strong to severe thunderstorms could continue to accompany a southeastward-moving cold front on D6/Wednesday from the southern Plains into the Ohio Valley and Northeast, though predictability remains low regarding the details at this time range. By D7/Thursday into D8/Friday, extended-range guidance generally suggests the potential for a mid/upper-level shortwave trough to move across the northern Rockies toward the northern High Plains. However, model spread remains rather high regarding the evolution of moisture return and any increasing severe potential in association with this system. Read more