Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, and no changes were needed with this update. ..Weinman.. 08/25/2024 .PREV DISCUSSION... /ISSUED 0142 AM CDT Sun Aug 25 2024/ ...Synopsis... A mid/upper-level trough is forecast to shift from the Northern Rockies into the Northern Plains Day 2/Monday. As this occurs, enhanced deep-layer flow is forecast to overspread portions of Wyoming near the base of the aforementioned trough, which will promote dry and breezy conditions. While locally elevated fire weather conditions are probable -- mainly during the afternoon with boundary-layer mixing -- fire weather conditions appear too spotty/brief to introduce an Elevated area at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more