Severe Storms

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF VA/NC AND NE/SD/MN/IA... ...SUMMARY... Scattered severe thunderstorms with large hail, damaging winds, and a few tornadoes are possible across parts of the Corn Belt in Iowa, Minnesota, Nebraska, and South Dakota this evening into tonight. Scattered damaging winds are possible across parts of Virginia and northern North Carolina this afternoon. ...SD/MN/IA/NE... A low-amplitude shortwave impulse along the international border over the northern Great Plains will progress across the Upper Midwest/Great Lakes and ON. A belt of seasonably strong mid-level westerlies should be centered this afternoon from central MN to Lake Huron. Elevated convection is expected to be ongoing at 12Z across parts of the eastern Dakotas into northern MN ahead of the mid-level impulse, amid a low-level warm theta-e advection regime. As this overspreads a preceding cool/dry surface airmass over the Upper Midwest, pronounced differential diabatic surface heating will strengthen a baroclinic zone across southeast SD bisecting IA to the southeast by late afternoon. Thunderstorm development in this time frame should be confined to along/northeast of the surface warm front across far eastern SD and southern MN. Large-scale ascent appears nebulous, but a strengthening low-level jet should aid in convection flanking to the southwest across the Mid-MO Valley during the evening. This may merge with high-based convection shifting east from western NE. Deep-layer shear will be sufficient for initial supercells that will probably grow upscale into multiple clusters and/or an MCS tonight. The latter may accelerate east-southeast for a time in the western IA vicinity before weakening during the early morning. A mix of all severe hazards are possible in this setup with hail being favored early and wind later. Moderately enlarged low-level hodographs should also support a tornado threat with any sustained supercell to QLCS evolution. ...VA/NC... 00Z HREF guidance supports scattered to numerous thunderstorms this afternoon with transient organizational structures that should be sufficient for a scattered damaging wind threat. This appears to be largely in response to the eastward progression of an MCV currently near the IN/OH/KY border. A compact belt of enhanced mid-level westerlies should overspread the northern periphery of ample MLCAPE emanating from the South Atlantic Coastal Plain. Multicell clusters that can progress towards a warmer/deeper boundary layer across the Piedmont and Coastal Plain should produce strong to sporadic severe gusts through early evening. ..Grams/Wendt.. 07/18/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1218 AM CDT Fri Jul 18 2025 Valid 191200Z - 201200Z ...Synopsis... A low-amplitude upper level trough will pivot through the Northwest on Saturday. In the lee of the northern Rockies, a surface low will deepen in central Montana. Mid-level moisture will be pushed slightly southward and eastward by the sagging upper trough in the Northwest. Additional thunderstorms are possible in the parts of the central/eastern Great Basin. However, PWAT values and slower storm motions do not suggest a significant threat for new ignitions. ...Columbia Basin and northern Nevada/southern Idaho... Elevated fire weather conditions are again expected in the Columbia Basin. With the core of the mid-level jet primarily being east of the region by the afternoon, the overall setup should favor slightly less strong wind coverage. Winds of 15-20 mph are still possible. RH may be a touch higher than on Friday with around 20% being probable during the afternoon. With the trough sagging southward and the surface low deepening, a zone of 15-20 mph (locally higher) winds is possible in parts of the northern Great Basin. RH could fall as low as 10-15% by the afternoon. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...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 1216 AM CDT Fri Jul 18 2025 Valid 181200Z - 191200Z ...Synopsis... Ridging aloft will be present across the southern half of the CONUS with a belt of stronger mid-level winds within the northern tier states. A weak upper-level low will remain nearly stationary in southern California/northern Baja. ...Northwest... Dry and windy conditions are most likely to occur within the Cascade gaps eastward into Columbia Basin and central Oregon. Here, surface winds of 15-20 mph will overlap afternoon RH of 15-20%. Some locally critical fire weather is possible in the Cascade gaps where winds will be stronger. However, RH may only briefly fall to critical levels. ...Northern Great Basin... Modest mid-level moisture return will be aided by the weak upper low in southern California. A few dry thunderstorms are possible on the northern/northwest fringe of the mid-level moisture. Storms may be a combination of both wet/dry modes due to relatively weak mid/upper-level flow. ..Wendt.. 07/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0523 Status Updates
STATUS REPORT ON WW 523 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NNE BIL TO 75 NW MLS. ..DEAN..07/18/25 ATTN...WFO...BYZ...GGW... STATUS REPORT FOR WS 523 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC017-025-079-087-103-180540- MT . MONTANA COUNTIES INCLUDED ARE CUSTER FALLON PRAIRIE ROSEBUD TREASURE THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0523 Status Updates
STATUS REPORT ON WW 523 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NNE BIL TO 75 NW MLS. ..DEAN..07/18/25 ATTN...WFO...BYZ...GGW... STATUS REPORT FOR WS 523 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC017-025-079-087-103-180540- MT . MONTANA COUNTIES INCLUDED ARE CUSTER FALLON PRAIRIE ROSEBUD TREASURE THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0523 Status Updates
STATUS REPORT ON WW 523 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NNE BIL TO 75 NW MLS. ..DEAN..07/18/25 ATTN...WFO...BYZ...GGW... STATUS REPORT FOR WS 523 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC017-025-079-087-103-180540- MT . MONTANA COUNTIES INCLUDED ARE CUSTER FALLON PRAIRIE ROSEBUD TREASURE THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 523 SEVERE TSTM MT 180250Z - 180800Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 523 NWS Storm Prediction Center Norman OK 850 PM MDT Thu Jul 17 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Montana * Effective this Thursday night and Friday morning from 850 PM until 200 AM MDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Two intense supercells continue to track southeastward into the watch area. Large hail and damaging wind gusts will remain possible for a few more hours with these storms. The severe thunderstorm watch area is approximately along and 40 statute miles north and south of a line from 90 miles west of Miles City MT to 15 miles southeast of Baker MT. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 522... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 29030. ...Hart Read more

WW 0522 Status Updates
STATUS REPORT ON WW 522 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 NNE BIL TO 65 SW GGW TO 65 NNW GGW. ..DEAN..07/18/25 ATTN...WFO...TFX...GGW... STATUS REPORT FOR WS 522 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC033-055-105-180440- MT . MONTANA COUNTIES INCLUDED ARE GARFIELD MCCONE VALLEY THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more