SPC May 13, 2025 2000 UTC Day 1 Convective Outlook

3 months 1 week ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue May 13 2025 Valid 132000Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA INTO THE SOUTHERN MID-ATLANTIC...CENTRAL GULF COAST STATES...AND THE NORTHERN HIGH PLAINS... ...SUMMARY... Marginally severe thunderstorms will be possible from this afternoon into tonight across parts of North Carolina, the Mid-Atlantic, central Gulf Coast states, and northern High Plains. ...DISCUSSION... No change is made to the outlook for this issuance. ..Broyles.. 05/13/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue May 13 2025/ ...North Carolina into the Southern Mid-Atlantic... A closed mid/upper-level low will continue to slowly meander from the TN Valley towards the central Appalachians through the period. An embedded mid-level shortwave trough will rotate northward across the Carolinas into the southern Mid-Atlantic by this evening. Stronger low/mid-level flow will tend to remain across the eastern Carolinas into southern VA today, with generally weaker winds aloft in closer proximity to the mid/upper low. A moist low-level airmass will remain in place over much of the Carolinas, central Appalachians, and southern Mid-Atlantic. But, poor mid-level lapse rates will tend to limit any more than weak instability from developing through this afternoon. Deep-layer shear away from the coast will also tend to remain muted, which should keep overall thunderstorm organization modest. Even with these forecast thermodynamic and kinematic limitations, some organization may occur with thunderstorms that develop and spread northward this afternoon. Isolated damaging winds appear to be the main threat with any loosely organized clusters that can form, but marginally severe hail could also occur with the strongest cores. A tornado or two also appears possible along a pseudo-warm front across northeast NC into southeast VA and vicinity, where low-level flow and shear are forecast to be modestly enhanced compared to locations farther west. ...Mississippi/Alabama... Morning showers and related cloudiness will temper diurnal destabilization to some extent across northern MS/AL this afternoon. But, renewed thunderstorm development still appears possible later today across this region, on the southern fringe of the slowly moving mid/upper low. Weak low-level westerly winds are expected to veer to northwesterly and gradually strengthen with height though mid levels. Related 30-40 kt of deep-layer shear will conditionally support organized updrafts, including the potential for a supercell with an associated hail/wind threat. The overall severe risk should remain quite isolated, which warrants maintaining the Marginal Risk with this update. ...Northern Plains... An amplified mid/upper-level trough will move eastward over the western states through tonight. A surface cold front is forecast to decelerate and eventually stall over parts of the Dakotas by this evening. Stronger mid/upper-level flow is expected to remain displaced to the west of this surface boundary. Even so, there are some indications in guidance that elevated thunderstorms posing a threat for isolated hail may impact parts of the northern Plains this evening into tonight. Weak instability should tend to limit the overall severe threat. Read more

SPC May 13, 2025 2000 UTC Day 1 Convective Outlook

3 months 1 week ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue May 13 2025 Valid 132000Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA INTO THE SOUTHERN MID-ATLANTIC...CENTRAL GULF COAST STATES...AND THE NORTHERN HIGH PLAINS... ...SUMMARY... Marginally severe thunderstorms will be possible from this afternoon into tonight across parts of North Carolina, the Mid-Atlantic, central Gulf Coast states, and northern High Plains. ...DISCUSSION... No change is made to the outlook for this issuance. ..Broyles.. 05/13/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue May 13 2025/ ...North Carolina into the Southern Mid-Atlantic... A closed mid/upper-level low will continue to slowly meander from the TN Valley towards the central Appalachians through the period. An embedded mid-level shortwave trough will rotate northward across the Carolinas into the southern Mid-Atlantic by this evening. Stronger low/mid-level flow will tend to remain across the eastern Carolinas into southern VA today, with generally weaker winds aloft in closer proximity to the mid/upper low. A moist low-level airmass will remain in place over much of the Carolinas, central Appalachians, and southern Mid-Atlantic. But, poor mid-level lapse rates will tend to limit any more than weak instability from developing through this afternoon. Deep-layer shear away from the coast will also tend to remain muted, which should keep overall thunderstorm organization modest. Even with these forecast thermodynamic and kinematic limitations, some organization may occur with thunderstorms that develop and spread northward this afternoon. Isolated damaging winds appear to be the main threat with any loosely organized clusters that can form, but marginally severe hail could also occur with the strongest cores. A tornado or two also appears possible along a pseudo-warm front across northeast NC into southeast VA and vicinity, where low-level flow and shear are forecast to be modestly enhanced compared to locations farther west. ...Mississippi/Alabama... Morning showers and related cloudiness will temper diurnal destabilization to some extent across northern MS/AL this afternoon. But, renewed thunderstorm development still appears possible later today across this region, on the southern fringe of the slowly moving mid/upper low. Weak low-level westerly winds are expected to veer to northwesterly and gradually strengthen with height though mid levels. Related 30-40 kt of deep-layer shear will conditionally support organized updrafts, including the potential for a supercell with an associated hail/wind threat. The overall severe risk should remain quite isolated, which warrants maintaining the Marginal Risk with this update. ...Northern Plains... An amplified mid/upper-level trough will move eastward over the western states through tonight. A surface cold front is forecast to decelerate and eventually stall over parts of the Dakotas by this evening. Stronger mid/upper-level flow is expected to remain displaced to the west of this surface boundary. Even so, there are some indications in guidance that elevated thunderstorms posing a threat for isolated hail may impact parts of the northern Plains this evening into tonight. Weak instability should tend to limit the overall severe threat. Read more

SPC May 13, 2025 2000 UTC Day 1 Convective Outlook

3 months 1 week ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue May 13 2025 Valid 132000Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA INTO THE SOUTHERN MID-ATLANTIC...CENTRAL GULF COAST STATES...AND THE NORTHERN HIGH PLAINS... ...SUMMARY... Marginally severe thunderstorms will be possible from this afternoon into tonight across parts of North Carolina, the Mid-Atlantic, central Gulf Coast states, and northern High Plains. ...DISCUSSION... No change is made to the outlook for this issuance. ..Broyles.. 05/13/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue May 13 2025/ ...North Carolina into the Southern Mid-Atlantic... A closed mid/upper-level low will continue to slowly meander from the TN Valley towards the central Appalachians through the period. An embedded mid-level shortwave trough will rotate northward across the Carolinas into the southern Mid-Atlantic by this evening. Stronger low/mid-level flow will tend to remain across the eastern Carolinas into southern VA today, with generally weaker winds aloft in closer proximity to the mid/upper low. A moist low-level airmass will remain in place over much of the Carolinas, central Appalachians, and southern Mid-Atlantic. But, poor mid-level lapse rates will tend to limit any more than weak instability from developing through this afternoon. Deep-layer shear away from the coast will also tend to remain muted, which should keep overall thunderstorm organization modest. Even with these forecast thermodynamic and kinematic limitations, some organization may occur with thunderstorms that develop and spread northward this afternoon. Isolated damaging winds appear to be the main threat with any loosely organized clusters that can form, but marginally severe hail could also occur with the strongest cores. A tornado or two also appears possible along a pseudo-warm front across northeast NC into southeast VA and vicinity, where low-level flow and shear are forecast to be modestly enhanced compared to locations farther west. ...Mississippi/Alabama... Morning showers and related cloudiness will temper diurnal destabilization to some extent across northern MS/AL this afternoon. But, renewed thunderstorm development still appears possible later today across this region, on the southern fringe of the slowly moving mid/upper low. Weak low-level westerly winds are expected to veer to northwesterly and gradually strengthen with height though mid levels. Related 30-40 kt of deep-layer shear will conditionally support organized updrafts, including the potential for a supercell with an associated hail/wind threat. The overall severe risk should remain quite isolated, which warrants maintaining the Marginal Risk with this update. ...Northern Plains... An amplified mid/upper-level trough will move eastward over the western states through tonight. A surface cold front is forecast to decelerate and eventually stall over parts of the Dakotas by this evening. Stronger mid/upper-level flow is expected to remain displaced to the west of this surface boundary. Even so, there are some indications in guidance that elevated thunderstorms posing a threat for isolated hail may impact parts of the northern Plains this evening into tonight. Weak instability should tend to limit the overall severe threat. Read more

SPC May 13, 2025 2000 UTC Day 1 Convective Outlook

3 months 1 week ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue May 13 2025 Valid 132000Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA INTO THE SOUTHERN MID-ATLANTIC...CENTRAL GULF COAST STATES...AND THE NORTHERN HIGH PLAINS... ...SUMMARY... Marginally severe thunderstorms will be possible from this afternoon into tonight across parts of North Carolina, the Mid-Atlantic, central Gulf Coast states, and northern High Plains. ...DISCUSSION... No change is made to the outlook for this issuance. ..Broyles.. 05/13/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue May 13 2025/ ...North Carolina into the Southern Mid-Atlantic... A closed mid/upper-level low will continue to slowly meander from the TN Valley towards the central Appalachians through the period. An embedded mid-level shortwave trough will rotate northward across the Carolinas into the southern Mid-Atlantic by this evening. Stronger low/mid-level flow will tend to remain across the eastern Carolinas into southern VA today, with generally weaker winds aloft in closer proximity to the mid/upper low. A moist low-level airmass will remain in place over much of the Carolinas, central Appalachians, and southern Mid-Atlantic. But, poor mid-level lapse rates will tend to limit any more than weak instability from developing through this afternoon. Deep-layer shear away from the coast will also tend to remain muted, which should keep overall thunderstorm organization modest. Even with these forecast thermodynamic and kinematic limitations, some organization may occur with thunderstorms that develop and spread northward this afternoon. Isolated damaging winds appear to be the main threat with any loosely organized clusters that can form, but marginally severe hail could also occur with the strongest cores. A tornado or two also appears possible along a pseudo-warm front across northeast NC into southeast VA and vicinity, where low-level flow and shear are forecast to be modestly enhanced compared to locations farther west. ...Mississippi/Alabama... Morning showers and related cloudiness will temper diurnal destabilization to some extent across northern MS/AL this afternoon. But, renewed thunderstorm development still appears possible later today across this region, on the southern fringe of the slowly moving mid/upper low. Weak low-level westerly winds are expected to veer to northwesterly and gradually strengthen with height though mid levels. Related 30-40 kt of deep-layer shear will conditionally support organized updrafts, including the potential for a supercell with an associated hail/wind threat. The overall severe risk should remain quite isolated, which warrants maintaining the Marginal Risk with this update. ...Northern Plains... An amplified mid/upper-level trough will move eastward over the western states through tonight. A surface cold front is forecast to decelerate and eventually stall over parts of the Dakotas by this evening. Stronger mid/upper-level flow is expected to remain displaced to the west of this surface boundary. Even so, there are some indications in guidance that elevated thunderstorms posing a threat for isolated hail may impact parts of the northern Plains this evening into tonight. Weak instability should tend to limit the overall severe threat. Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

3 months 1 week ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue May 13 2025 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST... Minor adjustments were made to bring the Elevated area further north into northwestern New Mexico and far eastern Arizona to account for latest trends in ensemble guidance. Otherwise, the outlook remains on track. See previous discussion below for more information. ..Thornton.. 05/13/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue May 13 2025/ ...Synopsis... The upper trough over the western US will continue to intensify as it emerges over the Rockies and onto the Plains Wednesday. Strong mid-level flow will strengthen a lee cyclone with a trailing cold front and dryline across the Great Plains. Dry westerly flow is likely over the Southwest where critical fire-weather conditions are expected. A more conditional threat for locally elevated fire-weather conditions exist over the Plains and Midwest ahead of the cold front. ...Southwest... As the main upper trough begins to move eastward over the Plains, the fire weather threat will persist for portions of Southwest. Moderate mid-level flow at the base of the upper-trough will support westerly downslope winds to 20-25 mph across southern New Mexico and eastern AZ Wednesday afternoon and evening. Amidst a very dry surface pattern with little recent rainfall and abnormally warm temperatures, RH values below 15% are likely. With sufficient fuels in place, and expanding in coverage from recent drying, widespread critical fire-weather conditions are likely Wednesday. ...Central plains and upper Midwest... As the upper trough moves eastward, a lee trough/dryline will gradually sharpen across the central CONUS. To the west, dry downslope flow is possible over parts of the central/northern Plains into the Upper Midwest. With RH minimums below 30% and wind gusting to 20 mph, some elevated fire-weather threat may be possible across parts of CO/KS and NE into the Dakotas. However, the strongest meteorological conditions are not expected to overlap with areas of supportive fuels given rainfall over the past week. Increasing surface moisture and some precipitation potential with the advancing cold front may further limit any appreciable overlap. This will favor a more localized threat with only isolated elevated fire-weather conditions expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC MD 775

3 months 1 week ago
MD 0775 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEASTERN SOUTH CAROLINA INTO CENTRAL NORTH CAROLINA
Mesoscale Discussion 0775 NWS Storm Prediction Center Norman OK 1247 PM CDT Tue May 13 2025 Areas affected...Northeastern South Carolina into central North Carolina Concerning...Severe potential...Watch unlikely Valid 131747Z - 131945Z Probability of Watch Issuance...5 percent SUMMARY...Isolated large hail and damaging wind gusts are possible with convection this afternoon. DISCUSSION...A shortwave perturbation around the Mid-South upper low has promoted the development of convection along parts of the NC/SC border. Additional storms are possible within this very moist, uncapped airmass along the Atlantic sea breeze or other localized areas of convergence. The most organized storms can be expected closer to the coast where effective shear values are greater. Large hail and damaging winds will likely be the primary threats with this activity. A weak warm front feature from northeast North Carolina into Virginia continues to lift northward. Given the boundary motion away from the ongoing storms, the tornado threat will likely remain low. ..Wendt/Gleason.. 05/13/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RAH...ILM...CAE...GSP... LAT...LON 33998075 35518067 36148034 36077993 35447889 34897834 34347804 34007830 33777885 33537909 33717962 33718025 33998075 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more

SPC May 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

3 months 1 week ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Tue May 13 2025 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF WISCONSIN... ...SUMMARY... Scattered severe thunderstorms are likely across parts of the western Great Lakes states and into parts of the Midwest Thursday afternoon and evening. Very large hail and a few tornadoes may occur. A more isolated/conditional severe threat will extend southwestward from western Kentucky into Arkansas late. ...Synopsis... An upper low will deepen over the northern Plains as a midlevel wave ejects northeastward toward the upper MS Valley. A surface low will also deepen over ND/MN, with occlusion. Extending southeast from the low will be a warm front, which will rapidly jump into northern MN and WI by late afternoon, and through much of Lower MI during the evening. Southeast winds near this boundary will bring mid to perhaps upper 60s F dewpoints northwestward, resulting in areas of strong instability. Given the fast motion of the shortwave trough and strongly veering winds in the low-levels, the primary severe risk area may be relatively narrow. The main front/dryline will stall near the OH River or Mid MS Valley and southwestward toward the Ozarks. This corridor, primarily later in the evening, will likely foster isolated severe storms as well. Elsewhere, a lingering upper trough will exit the Northeast, and warm advection on the backside of this feature may support isolated strong to severe storms from parts of PA into the Mid Atlantic during the day. ...Upper MS Valley/Great Lakes/Midwest... Models are in good agreement depicting a strong convective signal near the MN/WI border by 20Z or so, with increasing coverage points east through evening. Forecast soundings across WI and vicinity depict steep lapse rates aloft and hodographs favoring supercells. A strong tornado cannot be ruled out given the very favorable thermodynamics, including a slight capping inversion atop the moist boundary layer in combination with 200-300 m2/s2 ESRH. Southeast of the Enhanced Risk area into IL and IN, storm coverage looks to be more isolated. However, any supercells in this area will have the same significant hail and tornado potential as points north. This activity would likely wait until late in the day/after 21Z and closer to 00Z when heating is maximized to break the cap. Nocturnal severe storms will also be likely across much of Lower MI, northern IN and OH as activity moves in from the west. Supercells producing large hail again appear likely. ...OH Valley into AR Late... The aforementioned stalled boundary will be situated beneath persistent southwest flow at 850 mb Thursday evening and overnight. Robust moisture/high theta-e will be in place from eastern OK into the OH Valley, and scattered storms are likely to develop overnight. This area is a bit more conditional in terms of coverage of severe, but clearly large hail will be possible. A brief tornado may occur as well although hodographs will be primarily straight by this time. ..Jewell.. 05/13/2025 Read more