Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1144 AM CDT Fri Sep 12 2025 Valid 121700Z - 131200Z ...NO CRITICAL AREAS... A mid-level trough with associated lift and instability will continue to support widespread thunderstorms across primarily the mountainous terrain of the Interior West today. A few lightning fire starts are still possible, but fuel receptiveness remains less than ideal for widespread ignitions across the region due to antecedent and expected rainfall. ..Williams.. 09/12/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Fri Sep 12 2025/ ...Synopsis... A mid-level trough will overspread the Interior West as upper ridging persists over the central U.S. today. The broad upper troughing west of the Rockies will encourage the widespread lifting of a buoyant airmass, supporting scattered to numerous thunderstorms from the Great Basin to the northern Rockies and points east. Most of these storms are expected to be on the wet side, and given multiple past days of scattered to numerous thunderstorms, fuels are not expected to be quite as dry as in previous days/weeks. While a couple of lightning-induced fire ignitions are possible, the overall threat seems too sparse to warrant isolated dry thunderstorm highlights this outlook. ...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 1144 AM CDT Fri Sep 12 2025 Valid 121700Z - 131200Z ...NO CRITICAL AREAS... A mid-level trough with associated lift and instability will continue to support widespread thunderstorms across primarily the mountainous terrain of the Interior West today. A few lightning fire starts are still possible, but fuel receptiveness remains less than ideal for widespread ignitions across the region due to antecedent and expected rainfall. ..Williams.. 09/12/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Fri Sep 12 2025/ ...Synopsis... A mid-level trough will overspread the Interior West as upper ridging persists over the central U.S. today. The broad upper troughing west of the Rockies will encourage the widespread lifting of a buoyant airmass, supporting scattered to numerous thunderstorms from the Great Basin to the northern Rockies and points east. Most of these storms are expected to be on the wet side, and given multiple past days of scattered to numerous thunderstorms, fuels are not expected to be quite as dry as in previous days/weeks. While a couple of lightning-induced fire ignitions are possible, the overall threat seems too sparse to warrant isolated dry thunderstorm highlights this outlook. ...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 1144 AM CDT Fri Sep 12 2025 Valid 121700Z - 131200Z ...NO CRITICAL AREAS... A mid-level trough with associated lift and instability will continue to support widespread thunderstorms across primarily the mountainous terrain of the Interior West today. A few lightning fire starts are still possible, but fuel receptiveness remains less than ideal for widespread ignitions across the region due to antecedent and expected rainfall. ..Williams.. 09/12/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Fri Sep 12 2025/ ...Synopsis... A mid-level trough will overspread the Interior West as upper ridging persists over the central U.S. today. The broad upper troughing west of the Rockies will encourage the widespread lifting of a buoyant airmass, supporting scattered to numerous thunderstorms from the Great Basin to the northern Rockies and points east. Most of these storms are expected to be on the wet side, and given multiple past days of scattered to numerous thunderstorms, fuels are not expected to be quite as dry as in previous days/weeks. While a couple of lightning-induced fire ignitions are possible, the overall threat seems too sparse to warrant isolated dry thunderstorm highlights this outlook. ...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 1144 AM CDT Fri Sep 12 2025 Valid 121700Z - 131200Z ...NO CRITICAL AREAS... A mid-level trough with associated lift and instability will continue to support widespread thunderstorms across primarily the mountainous terrain of the Interior West today. A few lightning fire starts are still possible, but fuel receptiveness remains less than ideal for widespread ignitions across the region due to antecedent and expected rainfall. ..Williams.. 09/12/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Fri Sep 12 2025/ ...Synopsis... A mid-level trough will overspread the Interior West as upper ridging persists over the central U.S. today. The broad upper troughing west of the Rockies will encourage the widespread lifting of a buoyant airmass, supporting scattered to numerous thunderstorms from the Great Basin to the northern Rockies and points east. Most of these storms are expected to be on the wet side, and given multiple past days of scattered to numerous thunderstorms, fuels are not expected to be quite as dry as in previous days/weeks. While a couple of lightning-induced fire ignitions are possible, the overall threat seems too sparse to warrant isolated dry thunderstorm highlights this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2064 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF FAR NORTHEASTERN SOUTH DAKOTA AND CENTRAL/NORTHERN MINNESOTA
Mesoscale Discussion 2064 NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Sep 12 2025 Areas affected...portions of far northeastern South Dakota and central/northern Minnesota Concerning...Severe potential...Watch unlikely Valid 121617Z - 121715Z Probability of Watch Issuance...5 percent SUMMARY...Storms across central/northern Minnesota will pose a risk for small to severe hail. DISCUSSION...Thunderstorms ongoing across central Minnesota have produced occasional reports of hail up to 1 inch. Though MLCAPE is meager, NAM/RAP forecast soundings suggest there is ample MUCAPE aloft amid steep mid-level lapse rates and deep layer shear around 30-40 kts. This will continue to support a few instances of small to severe hail. Given the uncertainty on the duration and spatial coverage of this threat, a watch is unlikely. ..Thornton/Guyer.. 09/12/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...MPX...FGF...ABR... LAT...LON 46259647 47889535 48249448 48279355 48219296 48019250 47179222 46309236 46039247 45069606 45039720 45499759 45849735 46259647 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Fri Sep 12 2025 Valid 121630Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FOUR CORNERS AREA AND NORTHERN HIGH PLAINS... ...SUMMARY... Isolated severe storms will be possible today across the Four Corners area and central Rockies, with an increasing risk for severe storms into late afternoon and tonight across the northern Plains. ...Four Corners Region/central Rockies... Ahead of the prominent upper trough centered over the Great Basin and Lower Colorado River Valley, a lead mid-level impulse and related height falls and a strengthening of cyclonic flow aloft will influence the region. Cooling mid-level temperatures and a modestly warming boundary layer will further steepen lapse rates diurnally, with strong to severe storms expected to further develop into the afternoon. Relatively strong flow aloft with 40+ kt effective shear will support some supercell structures, with a related enhanced potential for severe hail, aside from locally gusty thunderstorm winds. More severe-favorable ingredients and a somewhat higher potential for severe storms appears to exist across the Four Corners vicinity including northwest New Mexico across western Colorado through the afternoon. ...Northern Plains including Eastern Montana/western Dakotas... Thunderstorm development/intensification is expected by late afternoon, initially on an isolated basis across central/eastern portions of Montana and Wyoming. Cooling mid-level temperatures and surface dew points in the 50s F will contribute to 500-1000 J/kg MLCAPE. Southwesterly deep-layer shear averaging 20-35 kt will be favorable for isolated storms with hail potential. Storm coverage should steadily increase into the evening toward the western Dakotas, aided by the arriving influence of greater forcing for ascent as located over the central Rockies early today. Hail potential will become more common this evening, with localized severe wind potential also modestly increasing. Strong/locally severe storms will potentially persist overnight across the western and central Dakotas. ...Northern/central Minnesota to northwest Wisconsin... Very isolated elevated severe storms, with hail as the most probable hazard, may continue east-southeastward today, semi-focused by elevated moisture transport well to the north of a warm front. ..Guyer/Jirak.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Fri Sep 12 2025 Valid 121300Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN MONTANA EAST ACROSS MUCH OF THE DAKOTAS...AND IN THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts and hail are possible across the Four Corners region, and from eastern Montana into the Dakotas. ...Synopsis... An upper trough will remain over the Intermountain West, making slow eastward progress through tonight. An embedded disturbance is forecast to move from CO into the Dakotas late in the day, while a midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primarily overnight as the upper-level ridge to the east gradually weakens. ...Eastern MT into the Dakotas... Thunderstorm development/intensification is expected across MT/WY east of a mid-level trough axis, where cool mid-level temperatures and surface dew points in the 50s will lead to MLCAPE in the 500 - locally 1000 J/kg range. Southwesterly deep-layer shear averaging 20-35 kts will be favorable for isolated storms with hail potential. As storms move/develop farther east across eastern MT/western ND/northwest SD towards evening, greater instability (MLCAPE on the order of 2000 J/kg) should result in a severe hail and wind risk with isolated stronger storms within a similarly-sheared environment. Although the low-level jet should be weaker in this area tonight, lingering instability across the western Dakotas suggests some continued severe risk, primarily for strong/damaging gusts, into the overnight hours. ...Four Corners Region... Scattered to numerous thunderstorms are expected to develop/intensify today from eastern AZ/southeast UT across western portions of NM/CO, within a moist plume on the eastern periphery of the mid-level trough. Cool mid-level temperatures will contribute to modest MLCAPE, with locally higher values (above 1000 J/kg) over southeastern AZ. A predominantly cellular or cluster mode is expected, with isolated stronger storms capable of marginally severe wind and hail. Storms should persist into the evening over western NM/CO, with a few stronger storms remaining possible. ..Bunting/Broyles.. 09/12/2025 Read more