Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sat Jul 26 2025 Valid 261700Z - 271200Z ...17z Update... The prior forecast remains valid with minor adjustments for the most recent guidance. Scattered thunderstorms, with isolated dry strikes, remain likely over portions of the northern Great Basin and northern Rockies this afternoon/evening. The edges of the IsoDryT area have been adjusted for recent heavier precipitation. Additional scattered storms are possible into parts of southwestern MT supporting some risk for lightning ignitions. Across the eastern Great Basin and Western Slope, dry/breezy conditions with RH below 15% and winds greater than 15 mph are likely this afternoon and evening from UT/AZ into parts of CO/WY. Minor adjustments were made to areas where recent rainfall has limited fuel availability. Otherwise, see the prior discussion for more information. ..Lyons.. 07/26/2025 .PREV DISCUSSION... /ISSUED 0138 AM CDT Sat Jul 26 2025/ ...Synopsis... A broad upper trough will overspread much of the western U.S. while upper ridging persists east of the Rockies today. Multiple embedded mid-level impulses will traverse the northern Great Basin into the northern Rockies during the afternoon, encouraging dry and breezy conditions across parts of the Great Basin into the Four Corners region, as well as thunderstorm development into the Pacific Northwest. By afternoon peak heating, southwesterly sustained surface winds will reach 15-25 mph as RH dips to 10-20 percent across the eastern Great Basin/Four Corners. Elevated highlights have been maintained given the presence of dry fuels. Farther to the northwest, from Northeast California to the Idaho/Montana border, adequate mid-level moisture and deep-layer ascent will support isolated to scattered thunderstorm development atop a dry boundary layer. High-based thunderstorms will produce a mix of wet and dry strikes atop receptive fuels, warranting the continuation of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1146 AM CDT Sat Jul 26 2025 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND MID-ATLANTIC... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts are possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will also be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Ahead of an upper low over northern California/western Nevada, midday water vapor imagery reflects a lead shortwave trough moving northeastward over northern Utah/eastern Idaho and western Wyoming. In this regime, forcing for ascent and gradual cooling aloft will occur through late today over northern Wyoming and southern/eastern Montana. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. This will initially occur across southern Montana and toward the Big Horns/northeast Wyoming. Additional high-based storm development is expected near the surface low and southward-extending surface trough into the central High Plains. Storms that move into the western Dakotas will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds, aside from some continued hail potential. As least some late-night severe risk will probably persist across North Dakota/eastern South Dakota into Minnesota. ...Midwest to Mid-Atlantic States/Delmarva... Multiple clusters of have persisted and/or reinvigorated early today in a corridor spanning north-central Illinois/northern Indiana, as well as central Pennsylvania. Moist/humid conditions will exist south of the convectively reinforced boundary and away from areas of persistent cloud debris (such as northward into Lower Michigan), with a reservoir of ample buoyancy contributing to a diurnal intensification of storms as multiple convectively enhanced mid-level disturbances interface with the effective front and nearby warm sector. The strongest storms will be capable of damaging winds, and a somewhat more favorable corridor for severe thunderstorms/wind damage appears to exist across the Mid-Atlantic States including south/southeast parts of Pennsylvania toward the Delmarva/Chesapeake Bay. ..Guyer/Thornton.. 07/26/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Sat Jul 26 2025 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT ACROSS PARTS OF THE DAKOTAS AND NORTHWEST MINNESOTA... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts will be possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Current water vapor loop shows a well-defined shortwave trough and associated mid-level speed max over parts of UT. As this feature tracks northeastward today, large-scale lift and subtle cooling aloft will overspread parts of northeast WY and central/eastern MT. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. Storms that move into western SD will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds. Latest model guidance suggests some potential for this activity to persist deep into the night and spread across eastern ND and parts of northern MN. Damaging winds will remain the main concern, along with some risk of hail and a tornado or two. ...Midwest into Mid-Atlantic Region... A large cluster of thunderstorms is ongoing this morning across parts of IA/IL. The associated outflow boundaries and clouds will result in an effective baroclinic zone today from northern MO/IL into southern Lower MI. Along and south of this boundary, hot/humid conditions will lead to large CAPE values. Scattered afternoon thunderstorms are expected, with the strongest cells capable of gusty/damaging winds. This regime will extend eastward into parts of PA and the Chesapeake Bay area with a few strong afternoon thunderstorms possible. ..Hart/Grams.. 07/26/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Sat Jul 26 2025 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT ACROSS PARTS OF THE DAKOTAS AND NORTHWEST MINNESOTA... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts will be possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Current water vapor loop shows a well-defined shortwave trough and associated mid-level speed max over parts of UT. As this feature tracks northeastward today, large-scale lift and subtle cooling aloft will overspread parts of northeast WY and central/eastern MT. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. Storms that move into western SD will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds. Latest model guidance suggests some potential for this activity to persist deep into the night and spread across eastern ND and parts of northern MN. Damaging winds will remain the main concern, along with some risk of hail and a tornado or two. ...Midwest into Mid-Atlantic Region... A large cluster of thunderstorms is ongoing this morning across parts of IA/IL. The associated outflow boundaries and clouds will result in an effective baroclinic zone today from northern MO/IL into southern Lower MI. Along and south of this boundary, hot/humid conditions will lead to large CAPE values. Scattered afternoon thunderstorms are expected, with the strongest cells capable of gusty/damaging winds. This regime will extend eastward into parts of PA and the Chesapeake Bay area with a few strong afternoon thunderstorms possible. ..Hart/Grams.. 07/26/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Sat Jul 26 2025 Valid 261300Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT ACROSS PARTS OF THE DAKOTAS AND NORTHWEST MINNESOTA... ...SUMMARY... Severe thunderstorms accompanied by damaging wind gusts will be possible this afternoon through tonight in parts of the northern Plains. Isolated strong to severe storms will be possible from the Ohio Valley and lower Great Lakes into the mid-Atlantic region, and across the central High Plains and much of Montana. ...Northern Plains... Current water vapor loop shows a well-defined shortwave trough and associated mid-level speed max over parts of UT. As this feature tracks northeastward today, large-scale lift and subtle cooling aloft will overspread parts of northeast WY and central/eastern MT. Northerly/upslope surface winds, combined with strong heating and moderate CAPE values, will promote the development of scattered high-based gusty thunderstorms by late afternoon. Storms that move into western SD will encounter progressively higher CAPE and likely grow upscale through the evening with a greater risk of organized severe winds. Latest model guidance suggests some potential for this activity to persist deep into the night and spread across eastern ND and parts of northern MN. Damaging winds will remain the main concern, along with some risk of hail and a tornado or two. ...Midwest into Mid-Atlantic Region... A large cluster of thunderstorms is ongoing this morning across parts of IA/IL. The associated outflow boundaries and clouds will result in an effective baroclinic zone today from northern MO/IL into southern Lower MI. Along and south of this boundary, hot/humid conditions will lead to large CAPE values. Scattered afternoon thunderstorms are expected, with the strongest cells capable of gusty/damaging winds. This regime will extend eastward into parts of PA and the Chesapeake Bay area with a few strong afternoon thunderstorms possible. ..Hart/Grams.. 07/26/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0352 AM CDT Sat Jul 26 2025 Valid 291200Z - 031200Z ...DISCUSSION... The upper-level pattern over the next week will generally feature an elongated upper ridge centered over the Southeast stretching into the Northwest. In the Northeast and nearby vicinity, upper-level cyclonic flow will be present. A belt of stronger mid-level winds will accompany that trough. Along the West Coast, a lower amplitude shortwave trough will slowly move northward along the coast. As the Northeast trough continues to shift east into late next week and the weekend, the surface cold front will continue to be pushed southward. Thunderstorms are likely to occur along and near this boundary given the hot and moist airmass to its south. While some severe risk could accompany this activity, stronger mid-level flow will become displaced farther and farther northward from the boundary each day. This leads to uncertainty in the overall magnitude of the severe threat from the Ohio Valley into the Mid-South/Southeast. Additional storms, with some severe potential could occur in parts of the Northwest with the approach of greater mid-level moisture and the trough. Again, the placement and intensity of this activity is uncertain. Even with a decrease in low-level moisture behind the surface front, remaining moisture will be pushing into the terrain of the northern Rockies. Along with some mid-level flow enhancement, strong to severe storms would be possible. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0352 AM CDT Sat Jul 26 2025 Valid 291200Z - 031200Z ...DISCUSSION... The upper-level pattern over the next week will generally feature an elongated upper ridge centered over the Southeast stretching into the Northwest. In the Northeast and nearby vicinity, upper-level cyclonic flow will be present. A belt of stronger mid-level winds will accompany that trough. Along the West Coast, a lower amplitude shortwave trough will slowly move northward along the coast. As the Northeast trough continues to shift east into late next week and the weekend, the surface cold front will continue to be pushed southward. Thunderstorms are likely to occur along and near this boundary given the hot and moist airmass to its south. While some severe risk could accompany this activity, stronger mid-level flow will become displaced farther and farther northward from the boundary each day. This leads to uncertainty in the overall magnitude of the severe threat from the Ohio Valley into the Mid-South/Southeast. Additional storms, with some severe potential could occur in parts of the Northwest with the approach of greater mid-level moisture and the trough. Again, the placement and intensity of this activity is uncertain. Even with a decrease in low-level moisture behind the surface front, remaining moisture will be pushing into the terrain of the northern Rockies. Along with some mid-level flow enhancement, strong to severe storms would be possible. Read more