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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will impinge on the West Coast as a preceding upper trough ejects into the Plains states tomorrow (Saturday). The net result will be another day of scattered to numerous thunderstorms across the Rockies toward the Four Corners region in association to the widespread lifting of a buoyant airmass with the upper trough. These storms will likely be more wet than dry, and will traverse areas that may see appreciable rainfall accumulations on Day 1, potentially dampening fuels in the process. While an instance or two of lightning-induced wildfire ignition cannot be ruled out, the coverage of such occurrences should be sparse at best. ..Squitieri.. 09/12/2025 ...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 0151 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will impinge on the West Coast as a preceding upper trough ejects into the Plains states tomorrow (Saturday). The net result will be another day of scattered to numerous thunderstorms across the Rockies toward the Four Corners region in association to the widespread lifting of a buoyant airmass with the upper trough. These storms will likely be more wet than dry, and will traverse areas that may see appreciable rainfall accumulations on Day 1, potentially dampening fuels in the process. While an instance or two of lightning-induced wildfire ignition cannot be ruled out, the coverage of such occurrences should be sparse at best. ..Squitieri.. 09/12/2025 ...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 0151 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will impinge on the West Coast as a preceding upper trough ejects into the Plains states tomorrow (Saturday). The net result will be another day of scattered to numerous thunderstorms across the Rockies toward the Four Corners region in association to the widespread lifting of a buoyant airmass with the upper trough. These storms will likely be more wet than dry, and will traverse areas that may see appreciable rainfall accumulations on Day 1, potentially dampening fuels in the process. While an instance or two of lightning-induced wildfire ignition cannot be ruled out, the coverage of such occurrences should be sparse at best. ..Squitieri.. 09/12/2025 ...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 0151 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will impinge on the West Coast as a preceding upper trough ejects into the Plains states tomorrow (Saturday). The net result will be another day of scattered to numerous thunderstorms across the Rockies toward the Four Corners region in association to the widespread lifting of a buoyant airmass with the upper trough. These storms will likely be more wet than dry, and will traverse areas that may see appreciable rainfall accumulations on Day 1, potentially dampening fuels in the process. While an instance or two of lightning-induced wildfire ignition cannot be ruled out, the coverage of such occurrences should be sparse at best. ..Squitieri.. 09/12/2025 ...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 0151 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will impinge on the West Coast as a preceding upper trough ejects into the Plains states tomorrow (Saturday). The net result will be another day of scattered to numerous thunderstorms across the Rockies toward the Four Corners region in association to the widespread lifting of a buoyant airmass with the upper trough. These storms will likely be more wet than dry, and will traverse areas that may see appreciable rainfall accumulations on Day 1, potentially dampening fuels in the process. While an instance or two of lightning-induced wildfire ignition cannot be ruled out, the coverage of such occurrences should be sparse at best. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...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 0150 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...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. ..Squitieri.. 09/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Sep 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS... ...SUMMARY... Strong to severe storms are possible over parts of the southern and central High Plains and northern Plains Saturday. ...Synopsis... The western upper trough will continue its slow progress eastward on Saturday. The trough is expected to eject into central Plains by early Sunday morning. A few embedded shortwave troughs will pivot into the northern Plains and stronger mid-level winds will extend into the southern Rockies. At the surface, a low in the northern Plains will become more diffuse during the period. ...Southern/Central High Plains... On the southern edge of the broad western trough, stronger mid-level flow will be perpendicular to the southern Rockies into part of the Front Range. Low-level moisture will advect into the regions given surface southeasterly winds. Moisture will be greatest in New Mexico with mid/upper 50s F dewpoints. Farther north, flow will become much more meridional and moisture will be more limited. Within the southern Rockies, cloud cover associated with the trough will generally keep low-level lapse rates weak. However, modestly steep mid-level lapse rates with the cooler air aloft and 35-40 kts of effective shear will promote some risk for a few supercell structures by the afternoon. Isolated large hail will be the main risk. While a similar hail threat will be present for much of the Front Range, this area is also more likely to receive greater surface heating. Steeper low-level lapse rates will support a threat for isolated severe gusts with the strongest storms. ...Northern Plains... Scattered thunderstorms will likely be ongoing at the start of the period. By this time, steeper mid-level lapse rates will likely have diminished for much of the western Dakotas into eastern Montana and Wyoming. This activity will be driven by a northward moving shortwave trough and low-level warm advection. Despite cloud cover complicating the low-level thermodynamic environment and the surface low gradually weakening with time, there may still be zone of greater potential in the eastern Dakotas where steeper mid-level lapse rates will be. Greater shear/forcing will overlap greater buoyancy during the afternoon in this area as well. The strongest storms, if they develop, will likely be near and east of the Missouri River. Small to isolated marginally severe hail appears to be the primary hazard. ...Upper Midwest... A weak shortwave trough is expected to move through southern Wisconsin into the southern Lake Michigan vicinity. This will promote a zone of warm advection that will allow potentially scattered storms to develop. While shear will be modestly enhanced with the shortwave, greater buoyancy and lapse rates will be displaced to the west. A stronger storm or two could occur, but limited confidence in greater severe storm coverage precludes probabilities. ..Wendt.. 09/12/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1233 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN MONTANA INTO THE DAKOTAS AND ACROSS THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts 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 the period. An upper disturbance is forecast to move from CO into the Dakotas late in the day, while a strong midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primary overnight as the Plains upper ridge gradually weakens. At the surface, a weak area of low pressure is forecast over SD, with a trough extending westward across WY and into the Great Basin during the afternoon with strong heating. Dewpoints in the 60s F will be common across the mid MO Valley, especially from MN into the Dakotas where surface winds will be backed north of the low. Rather veered/southwesterly 850 mb flow is forecast overnight, with only pockets of positive theta-e advection. ...Eastern MT into the Dakotas... Moderate instability will develop over much of the northern Plains, but beneath temporary upper ridging. Storms are most likely to form over eastern MT and WY, beneath cooler temperatures aloft and where less capping will exist. Isolated hail may occur with these widely scattered afternoon cells. Later in the evening, a few cells may persist into the western Dakotas with hail potential, and there appears to be a possibility of scattered damaging gusts as activity/outflow moves out of WY/CO and interacts with stronger instability over the Dakotas overnight. Given the lack of low-level jet support and uncertainty, will maintain 5% probabilities. ...Four Corners Region... Daytime heating combined with a midlevel moist plume and cooling aloft should yield scattered afternoon development over far eastern AZ and UT into western CO and NM. Instability will not be particularly strong, but likely sufficient for a few damaging gusts or marginal hail as the most prevalent storm mode is expected to be cellular with favorably long hodographs/veering with height. Some of this activity may persist well into the evening over NM. ..Jewell/Squitieri.. 09/12/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1233 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN MONTANA INTO THE DAKOTAS AND ACROSS THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts 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 the period. An upper disturbance is forecast to move from CO into the Dakotas late in the day, while a strong midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primary overnight as the Plains upper ridge gradually weakens. At the surface, a weak area of low pressure is forecast over SD, with a trough extending westward across WY and into the Great Basin during the afternoon with strong heating. Dewpoints in the 60s F will be common across the mid MO Valley, especially from MN into the Dakotas where surface winds will be backed north of the low. Rather veered/southwesterly 850 mb flow is forecast overnight, with only pockets of positive theta-e advection. ...Eastern MT into the Dakotas... Moderate instability will develop over much of the northern Plains, but beneath temporary upper ridging. Storms are most likely to form over eastern MT and WY, beneath cooler temperatures aloft and where less capping will exist. Isolated hail may occur with these widely scattered afternoon cells. Later in the evening, a few cells may persist into the western Dakotas with hail potential, and there appears to be a possibility of scattered damaging gusts as activity/outflow moves out of WY/CO and interacts with stronger instability over the Dakotas overnight. Given the lack of low-level jet support and uncertainty, will maintain 5% probabilities. ...Four Corners Region... Daytime heating combined with a midlevel moist plume and cooling aloft should yield scattered afternoon development over far eastern AZ and UT into western CO and NM. Instability will not be particularly strong, but likely sufficient for a few damaging gusts or marginal hail as the most prevalent storm mode is expected to be cellular with favorably long hodographs/veering with height. Some of this activity may persist well into the evening over NM. ..Jewell/Squitieri.. 09/12/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1233 AM CDT Fri Sep 12 2025 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN MONTANA INTO THE DAKOTAS AND ACROSS THE FOUR CORNERS REGION... ...SUMMARY... A few storms capable of isolated severe wind gusts 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 the period. An upper disturbance is forecast to move from CO into the Dakotas late in the day, while a strong midlevel jet rounds the base of the trough across AZ overnight. Gradual height falls will occur across the length of High Plains primary overnight as the Plains upper ridge gradually weakens. At the surface, a weak area of low pressure is forecast over SD, with a trough extending westward across WY and into the Great Basin during the afternoon with strong heating. Dewpoints in the 60s F will be common across the mid MO Valley, especially from MN into the Dakotas where surface winds will be backed north of the low. Rather veered/southwesterly 850 mb flow is forecast overnight, with only pockets of positive theta-e advection. ...Eastern MT into the Dakotas... Moderate instability will develop over much of the northern Plains, but beneath temporary upper ridging. Storms are most likely to form over eastern MT and WY, beneath cooler temperatures aloft and where less capping will exist. Isolated hail may occur with these widely scattered afternoon cells. Later in the evening, a few cells may persist into the western Dakotas with hail potential, and there appears to be a possibility of scattered damaging gusts as activity/outflow moves out of WY/CO and interacts with stronger instability over the Dakotas overnight. Given the lack of low-level jet support and uncertainty, will maintain 5% probabilities. ...Four Corners Region... Daytime heating combined with a midlevel moist plume and cooling aloft should yield scattered afternoon development over far eastern AZ and UT into western CO and NM. Instability will not be particularly strong, but likely sufficient for a few damaging gusts or marginal hail as the most prevalent storm mode is expected to be cellular with favorably long hodographs/veering with height. Some of this activity may persist well into the evening over NM. ..Jewell/Squitieri.. 09/12/2025 Read more