Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...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 0216 PM CDT Sat Jul 26 2025 Valid 271200Z - 281200Z ...Afternoon Update... Isolated dry thunderstorms remain likely from portions of northern CA and southern OR into the northern Rockies. While storm coverage should be scattered, inverted-v profiles (based on forecast soundings) show at least some lightning potential outside of the heavier wetting rain cores. Have adjusted the IsoDryT area for the latest guidance. ...Eastern Great Basin... On the western periphery of the upper ridge, slight enhancement of southwesterly flow loft will persist over eastern UT and parts of WY/CO. Deep mixing of the boundary layer will promote breezy afternoon surface winds of 15-20 mph. Low humidity of 15-20% will also be colocated with the stronger wind gusts. This could support a few hours of elevated fire-weather potential Sunday. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... Upper troughing will persist along the West Coast as the upper ridge continues to build over the central and eastern U.S. tomorrow (Sunday). Mid-level moisture along the upper trough will overspread a dry boundary layer, characterized by inverted-v profiles (based on forecast soundings). As such, a mix of wet and dry high-based thunderstorms is anticipated during the afternoon and evening hours across portions of the Pacific Northwest toward the northern Rockies. Given dry fuels over the region and associated potential for lightning induced ignitions, isolated dry thunderstorm highlights have been added. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat Jul 26 2025 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA...THE DAKOTAS...IOWA...MINNESOTA...AND WISCONSIN... ...SUMMARY... Severe thunderstorms are possible from the northern Rockies into the Dakotas and Upper Midwest. ...Southeast Montana and the Dakotas to Wisconsin... A couple of shortwave impulses are forecast to move eastward through westerly flow aloft on Sunday. At the surface, low pressure is forecast over SD, with a surface front expected to develop south/southeast from southeast MT to the Mid-MO Valley into early Monday. A very moist airmass will be in place ahead of the surface low/front across SD into parts of MN/IA/WI. This will support a broad area of strong to extreme instability. However, uncertainty persists, and is mainly a result of how convection and a potential MCS will develop in the Day 2/Sunday period and what impacts those storms may have on the boundary layer across parts of the Upper Midwest. Nevertheless, it appears likely isolated storms will develop near the surface low and within the post-frontal regime from southeast MT into the Black Hills vicinity. This activity will pose a risk of mainly strong/severe gusts and perhaps some marginal hail. With eastward extent across SD into MN/IA/WI, storms will likely form along the southward-advancing front. Some guidance depicts a modest low-level jet developing during the evening. Coupled with sufficient effective shear, and strong instability, upscale growth into an MCS is possible. Where this may occur is uncertain as previously mentioned outflow from prior convection may result in lingering inhibition. Some severe wind risk appears possible and the Marginal risk (level 1 of 5) will be maintained, though higher probabilities may be needed in subsequent outlooks. ...Central MT... Isolated thunderstorms will develop over higher terrain during the afternoon/evening as a shortwave trough migrates through the upper ridge over the Pacific Northwest. Sufficient moisture will be in place and relatively cool temperatures aloft will aid in MLCAPE values approaching 1000 J/kg. Effective shear magnitudes around 25-30 kt will support occasionally organized cells. A deeply mixed boundary layer will foster locally strong/damaging wind potential. ..Leitman.. 07/26/2025 Read more