Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Aug 16 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN GREAT PLAINS TO THE CORN BELT... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the Corn Belt and northern Great Plains, mainly during the late afternoon and evening on Monday. ...Corn Belt to the northern Great Plains... Large-scale pattern will feature retrogression of the mid/upper anticyclone from the southern Great Plains into the Southwest. An MCV should amplify as a result of D2 MCS development and act as a low-amplitude shortwave impulse drifting across the Upper Great Lakes. Ridging will build north towards the northern High Plains by early Tuesday. This evolution will yield a generally modest zonal mid-level flow regime over the North-Central States on Monday. Extensive but decaying convection should be ongoing at 12Z Monday from the Lake Superior/Upper MS Valley into IA and perhaps the Lower MO Valley. Pockets of stronger boundary-layer heating will be necessary for diurnal intensification with weaker mid-level lapse rates relative to prior days. Confidence is low in just how unstable the airmass will be in WI/IL on Monday afternoon. Still, will maintain a level 1-MRGL with a risk for isolated damaging winds. Farther west, steep mid-level lapse rates will foster moderate to large buoyancy from NE into eastern MT/western ND. Guidance has varying signals for widely scattered convective development, but it appears most probable over the central High Plains and Black Hills during the late afternoon and evening. Coverage is more nebulous in MT/ND as mid/upper ridging gradually builds, but deep-layer shear will be greater compared to farther south. A broad swath of low-probability severe remains appropriate with a mix of wind and hail possible. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE NORTHERN CONUS... ...SUMMARY... Isolated severe thunderstorms are possible, mainly during the late afternoon and evening Sunday from the Upper Midwest to the northern High Plains. Isolated damaging winds are possible on Sunday afternoon to early evening across the Northeast and New England. ...Upper Midwest... Decaying convective swaths will likely be ongoing at 12Z Sunday, centered on the eastern Dakotas to southern MN. The eastern lobe of this morning activity will aid in strengthening the quasi-stationary baroclinic zone, as differential boundary-layer heating occurs across it through the day. Presence of mid to upper ridging emanating north-northeast from the southern Great Plains anticyclone will remain a limiting factor to more robust severe potential. Still, drifting MCVs across the Dakotas in a modest southwesterly flow regime in conjunction with large buoyancy in the warm-moist sector should aid in scattered late-afternoon thunderstorm development. This appears most probable in the eastern SD to southwest MN vicinity, with isolated coverage trailing into central NE. A mix of isolated severe hail/wind initially should transition to mainly sporadic strong to severe gusts through the evening as slow-moving clusters/MCSs develop. A brief tornado is also possible with any transient supercell structures near the front. ...Northern High Plains... Primary severe potential should emanate out of late afternoon convection initiating off the higher terrain of southern MT and separately in the Black Hills vicinity. A modest combination of deep-layer shear and large-scale ascent suggests mainly a strong to isolated severe threat should be expected as high-based convection spreads northeast across eastern MT. The presence of weak surface/low-level should modulate the eastern extent of severe potential on Sunday evening. ...Northeast/New England... A shortwave trough will progress across the St. Lawrence Valley towards the Canadian Maritimes and northern New England through Sunday afternoon. A cold front will push southeastward through the day with isolated to widely scattered thunderstorms expected along it during the afternoon. Buoyancy appears likely to be weak and will remain a limiting factor to more robust severe potential. More favorable deep-layer shear will exist in New England where localized damaging winds and small hail should be favored. Farther southwest, multicell clustering should be dominant with isolated damaging winds from sporadic strong gusts. ..Grams.. 08/16/2025 Read more