Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Wed Aug 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS TO THE UPPER MIDWEST... ...SUMMARY... Strong to locally severe thunderstorms are possible Friday from parts of the central and northern High Plains into the Upper Midwest. ...Northern/Central High Plains to Upper Midwest... An upper cyclone over the Canadian Prairies and its attendant trough will develop southeast across portions of the northern/central Plains and Upper Midwest/Great Lakes on Friday. At the surface, a cold front will develop south/southeast across the region. A seasonally moist airmass will be in place near and ahead of the front. A narrow corridor of 1000-3000 J/kg MLCAPE is forecast ahead of the front from the WY/CO High Plains eastward across parts of NE and northeast into southern MN and northern/central WI. Isolated to widely scattered thunderstorms are expected to develop during the afternoon across portions of WI/MN and the U.P. of MI. closer to the surface low over Ontario. Vertical shear is expected to remain modest, with stronger shear likely trailing the cold front. Nevertheless, steepened low-level lapse rates where stronger heating occurs could support sporadic strong to severe gusts. Additional storms are expected to develop in the post-frontal upslope regime across parts of eastern WY and northeast CO during the late afternoon/evening. This activity may eventually become a forward propagating cluster across NE during the nighttime hours as the surface cold front develops southward toward the KS border. Forecast soundings indicated sufficient deep shear and elongated/straight hodographs will be present amid steep midlevel lapse rates. Isolated large hail may be possible initially, with an increasing chance for isolated damaging gusts if sufficient clustering can occur further east into NE and vicinity. ..Leitman.. 08/20/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...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 0100 PM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z The IsoDryT area was expanded based on the latest high-resolution forecast guidance. High-based showers and thunderstorms may be ongoing tomorrow morning over portions of northern Utah into western/central Wyoming. High-based showers and thunderstorms may continue overnight from east-central Nevada through central Utah as well. Locally elevated conditions are likely across swaths of the Great Basin into Wyoming and Colorado due to hot/dry/breezy conditions in pre/post-frontal environments. Additionally, a thermal trough will strengthen over the West Coast tomorrow with hot/dry/unstable and locally breezy conditions expected from southern California into the Pacific Northwest, west of the Cascades. ..Nauslar.. 08/20/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Wed Aug 20 2025/ ...Synopsis... The strong ridge over the western US is expected to continue to break down under the shortwave trough passing through the northern Rockies. This will support continued advection of monsoon moisture northward into the Great Basin and parts of southern California. By Thursday afternoon, PWAT values are likely to be between 0.5-0.8" with a dry sub-cloud layer and steep low-level lapse rates. Despite slower storm motions and isolated coverage over Utah and parts of Nevada, little wetting rainfall is expected. This should support isolated dry thunderstorm potential the under the upper high and into portions of eastern Idaho and western Wyoming. With dry fuels in place, some lightning ignitions are possible. In addition to the potential for thunderstorms, very warm and unstable conditions are expected on the periphery of the deeper monsoon moisture surge over parts of the southern Great Basin and southern California. Steep mid-level lapse rates and marginal buoyancy will support unstable conditions over much of the Southwest. This could support plume dominated fire growth and pyroconvection near large active fires, with localized extreme fire behavior possible. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Wed Aug 20 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DAKOTAS INTO MINNESOTA... ...SUMMARY... An isolated severe threat is expected to develop Thursday into Thursday night over parts of the Dakotas into Minnesota, with severe gusts and hail possible. ...Northern Plains into Minnesota... An upper shortwave trough/cyclone will deepen and develop east across the Canadian Prairies on Thursday. This will result in dampening of the upper ridge/height falls across the northern Plains vicinity. Early in the day, a weak shortwave impulse and remnant convection/cloud debris will move across portions of ND/MN. Meanwhile, a cold front will develop east/southeast across the Dakotas into northern MN through early Friday. A corridor of rich boundary layer moisture with dewpoints generally in the mid 60s to near 70 F will be in place ahead of the cold front. However, stronger forcing for ascent will not arrive until later in the evening/overnight. It is unclear how much diurnal convection may develop due to weaker forcing and capping. If a storm can form ahead of the front during the afternoon, a corridor of 2000-3000 J/kg MLCAPE will be in place amid 30+ kt effective shear. Strong gusts and hail would be possible with cellular activity through early evening. More likely, convection will develop during the evening/nighttime hours across parts of the region. Initial storms may develop in the post-frontal upslope regime across eastern WY/western SD and develop east across SD overnight. It is unclear how intense these initial storms further west will be, and probabilities may need to be expanded westward in subsequent outlooks if confidence increases. Once storms interact with better moisture/instability further east, isolated severe gusts or marginal hail will be possible. ..Leitman.. 08/20/2025 Read more