Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Jun 21 2025 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHERN PORTIONS OF NEW YORK AND VERMONT... CORRECTED FOR SPELLING IN SUMMARY ...SUMMARY... Thunderstorms associated with severe wind gusts and hail will be possible tonight across New York and New England. Isolated severe storms will also be possible across portions of the Great Lakes, the northern High Plains and Middle Missouri Valley. ...Great Lakes... Strong/intermittently severe thunderstorms continue across the northern Lower Peninsula of Michigan this morning, associated with the long-lived severe MCS that moved across the northern Plains/upper Midwest Friday afternoon and night. Although the immediate downstream environment is only slowly warming due to the presence of mid/high-level clouds, some slow destabilization is occurring. This will maintain at least some continued risk for a strong/severe storm through early afternoon across northern Lower MI and adjacent waters of Lake Huron. Across the MI Upper Peninsula, a warm front is expected to sharpen across this area, along with rising heights in the wake of the convectively-augmented vorticity maximum now moving through southern Ontario. Heating of a very moist boundary layer will result in strong to extreme instability (MLCAPE in excess of 3000 J/kg), however the presence of a pronounced cap should suppress storms during the afternoon. As a modest low-level jet strengthens this evening, isolated elevated severe storms will be possible on the immediate cool side of the front, within an environment supportive of organized storms including supercells. Large hail and damaging winds will be possible. ...NY into Western New England... Thunderstorms moving across Lake Huron/southwestern Ontario at 16z will continue east, and most morning CAM guidance suggests storms will remain west of western NY. Of greater concern will be the potential for storms to move into northern NY/western New England late tonight ahead of a southeast-moving cold front, where modest destabilization and strong deep-layer shear will support storm organization. Morning hi-res guidance supports a loosely organized linear structure, and perhaps supercells with an attendant risk for strong winds and severe hail late tonight. The Level 2/Slight Risk has been expanded east into northern VT based on this expectation. ...Eastern MT into Western ND... Isolated thunderstorms have weakened over eastern MT this morning, with additional isolated redevelopment possible this afternoon and tonight as ascent associated with minor perturbations within southwest mid-level flow moves across the area. Modest instability and strong deep-layer shear will support updraft organization and a risk for severe hail and/or damaging gusts. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to move little this afternoon, with low-level moisture advection throughout the warm sector east of this low. Air mass recovery/modification following the overnight MCS is expected, and this will contribute to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises will occur within the large-scale environment. Additionally, warm mid-level temperatures (16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection this afternoon. Isolated thunderstorm development will be possible mainly this evening as a low-level jet strengthens, with a risk for severe wind and isolated hail. ..Bunting.. 06/21/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Jun 21 2025 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHERN PORTIONS OF NEW YORK AND VERMONT... CORRECTED FOR SPELLING IN SUMMARY ...SUMMARY... Thunderstorms associated with severe wind gusts and hail will be possible tonight across New York and New England. Isolated severe storms will also be possible across portions of the Great Lakes, the northern High Plains and Middle Missouri Valley. ...Great Lakes... Strong/intermittently severe thunderstorms continue across the northern Lower Peninsula of Michigan this morning, associated with the long-lived severe MCS that moved across the northern Plains/upper Midwest Friday afternoon and night. Although the immediate downstream environment is only slowly warming due to the presence of mid/high-level clouds, some slow destabilization is occurring. This will maintain at least some continued risk for a strong/severe storm through early afternoon across northern Lower MI and adjacent waters of Lake Huron. Across the MI Upper Peninsula, a warm front is expected to sharpen across this area, along with rising heights in the wake of the convectively-augmented vorticity maximum now moving through southern Ontario. Heating of a very moist boundary layer will result in strong to extreme instability (MLCAPE in excess of 3000 J/kg), however the presence of a pronounced cap should suppress storms during the afternoon. As a modest low-level jet strengthens this evening, isolated elevated severe storms will be possible on the immediate cool side of the front, within an environment supportive of organized storms including supercells. Large hail and damaging winds will be possible. ...NY into Western New England... Thunderstorms moving across Lake Huron/southwestern Ontario at 16z will continue east, and most morning CAM guidance suggests storms will remain west of western NY. Of greater concern will be the potential for storms to move into northern NY/western New England late tonight ahead of a southeast-moving cold front, where modest destabilization and strong deep-layer shear will support storm organization. Morning hi-res guidance supports a loosely organized linear structure, and perhaps supercells with an attendant risk for strong winds and severe hail late tonight. The Level 2/Slight Risk has been expanded east into northern VT based on this expectation. ...Eastern MT into Western ND... Isolated thunderstorms have weakened over eastern MT this morning, with additional isolated redevelopment possible this afternoon and tonight as ascent associated with minor perturbations within southwest mid-level flow moves across the area. Modest instability and strong deep-layer shear will support updraft organization and a risk for severe hail and/or damaging gusts. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to move little this afternoon, with low-level moisture advection throughout the warm sector east of this low. Air mass recovery/modification following the overnight MCS is expected, and this will contribute to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises will occur within the large-scale environment. Additionally, warm mid-level temperatures (16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection this afternoon. Isolated thunderstorm development will be possible mainly this evening as a low-level jet strengthens, with a risk for severe wind and isolated hail. ..Bunting.. 06/21/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Jun 21 2025 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHERN PORTIONS OF NEW YORK AND VERMONT... CORRECTED FOR SPELLING IN SUMMARY ...SUMMARY... Thunderstorms associated with severe wind gusts and hail will be possible tonight across New York and New England. Isolated severe storms will also be possible across portions of the Great Lakes, the northern High Plains and Middle Missouri Valley. ...Great Lakes... Strong/intermittently severe thunderstorms continue across the northern Lower Peninsula of Michigan this morning, associated with the long-lived severe MCS that moved across the northern Plains/upper Midwest Friday afternoon and night. Although the immediate downstream environment is only slowly warming due to the presence of mid/high-level clouds, some slow destabilization is occurring. This will maintain at least some continued risk for a strong/severe storm through early afternoon across northern Lower MI and adjacent waters of Lake Huron. Across the MI Upper Peninsula, a warm front is expected to sharpen across this area, along with rising heights in the wake of the convectively-augmented vorticity maximum now moving through southern Ontario. Heating of a very moist boundary layer will result in strong to extreme instability (MLCAPE in excess of 3000 J/kg), however the presence of a pronounced cap should suppress storms during the afternoon. As a modest low-level jet strengthens this evening, isolated elevated severe storms will be possible on the immediate cool side of the front, within an environment supportive of organized storms including supercells. Large hail and damaging winds will be possible. ...NY into Western New England... Thunderstorms moving across Lake Huron/southwestern Ontario at 16z will continue east, and most morning CAM guidance suggests storms will remain west of western NY. Of greater concern will be the potential for storms to move into northern NY/western New England late tonight ahead of a southeast-moving cold front, where modest destabilization and strong deep-layer shear will support storm organization. Morning hi-res guidance supports a loosely organized linear structure, and perhaps supercells with an attendant risk for strong winds and severe hail late tonight. The Level 2/Slight Risk has been expanded east into northern VT based on this expectation. ...Eastern MT into Western ND... Isolated thunderstorms have weakened over eastern MT this morning, with additional isolated redevelopment possible this afternoon and tonight as ascent associated with minor perturbations within southwest mid-level flow moves across the area. Modest instability and strong deep-layer shear will support updraft organization and a risk for severe hail and/or damaging gusts. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to move little this afternoon, with low-level moisture advection throughout the warm sector east of this low. Air mass recovery/modification following the overnight MCS is expected, and this will contribute to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises will occur within the large-scale environment. Additionally, warm mid-level temperatures (16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection this afternoon. Isolated thunderstorm development will be possible mainly this evening as a low-level jet strengthens, with a risk for severe wind and isolated hail. ..Bunting.. 06/21/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Jun 21 2025 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHERN PORTIONS OF NEW YORK AND VERMONT... CORRECTED FOR SPELLING IN SUMMARY ...SUMMARY... Thunderstorms associated with severe wind gusts and hail will be possible tonight across New York and New England. Isolated severe storms will also be possible across portions of the Great Lakes, the northern High Plains and Middle Missouri Valley. ...Great Lakes... Strong/intermittently severe thunderstorms continue across the northern Lower Peninsula of Michigan this morning, associated with the long-lived severe MCS that moved across the northern Plains/upper Midwest Friday afternoon and night. Although the immediate downstream environment is only slowly warming due to the presence of mid/high-level clouds, some slow destabilization is occurring. This will maintain at least some continued risk for a strong/severe storm through early afternoon across northern Lower MI and adjacent waters of Lake Huron. Across the MI Upper Peninsula, a warm front is expected to sharpen across this area, along with rising heights in the wake of the convectively-augmented vorticity maximum now moving through southern Ontario. Heating of a very moist boundary layer will result in strong to extreme instability (MLCAPE in excess of 3000 J/kg), however the presence of a pronounced cap should suppress storms during the afternoon. As a modest low-level jet strengthens this evening, isolated elevated severe storms will be possible on the immediate cool side of the front, within an environment supportive of organized storms including supercells. Large hail and damaging winds will be possible. ...NY into Western New England... Thunderstorms moving across Lake Huron/southwestern Ontario at 16z will continue east, and most morning CAM guidance suggests storms will remain west of western NY. Of greater concern will be the potential for storms to move into northern NY/western New England late tonight ahead of a southeast-moving cold front, where modest destabilization and strong deep-layer shear will support storm organization. Morning hi-res guidance supports a loosely organized linear structure, and perhaps supercells with an attendant risk for strong winds and severe hail late tonight. The Level 2/Slight Risk has been expanded east into northern VT based on this expectation. ...Eastern MT into Western ND... Isolated thunderstorms have weakened over eastern MT this morning, with additional isolated redevelopment possible this afternoon and tonight as ascent associated with minor perturbations within southwest mid-level flow moves across the area. Modest instability and strong deep-layer shear will support updraft organization and a risk for severe hail and/or damaging gusts. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to move little this afternoon, with low-level moisture advection throughout the warm sector east of this low. Air mass recovery/modification following the overnight MCS is expected, and this will contribute to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises will occur within the large-scale environment. Additionally, warm mid-level temperatures (16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection this afternoon. Isolated thunderstorm development will be possible mainly this evening as a low-level jet strengthens, with a risk for severe wind and isolated hail. ..Bunting.. 06/21/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Jun 21 2025 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHERN PORTIONS OF NEW YORK AND VERMONT... CORRECTED FOR SPELLING IN SUMMARY ...SUMMARY... Thunderstorms associated with severe wind gusts and hail will be possible tonight across New York and New England. Isolated severe storms will also be possible across portions of the Great Lakes, the northern High Plains and Middle Missouri Valley. ...Great Lakes... Strong/intermittently severe thunderstorms continue across the northern Lower Peninsula of Michigan this morning, associated with the long-lived severe MCS that moved across the northern Plains/upper Midwest Friday afternoon and night. Although the immediate downstream environment is only slowly warming due to the presence of mid/high-level clouds, some slow destabilization is occurring. This will maintain at least some continued risk for a strong/severe storm through early afternoon across northern Lower MI and adjacent waters of Lake Huron. Across the MI Upper Peninsula, a warm front is expected to sharpen across this area, along with rising heights in the wake of the convectively-augmented vorticity maximum now moving through southern Ontario. Heating of a very moist boundary layer will result in strong to extreme instability (MLCAPE in excess of 3000 J/kg), however the presence of a pronounced cap should suppress storms during the afternoon. As a modest low-level jet strengthens this evening, isolated elevated severe storms will be possible on the immediate cool side of the front, within an environment supportive of organized storms including supercells. Large hail and damaging winds will be possible. ...NY into Western New England... Thunderstorms moving across Lake Huron/southwestern Ontario at 16z will continue east, and most morning CAM guidance suggests storms will remain west of western NY. Of greater concern will be the potential for storms to move into northern NY/western New England late tonight ahead of a southeast-moving cold front, where modest destabilization and strong deep-layer shear will support storm organization. Morning hi-res guidance supports a loosely organized linear structure, and perhaps supercells with an attendant risk for strong winds and severe hail late tonight. The Level 2/Slight Risk has been expanded east into northern VT based on this expectation. ...Eastern MT into Western ND... Isolated thunderstorms have weakened over eastern MT this morning, with additional isolated redevelopment possible this afternoon and tonight as ascent associated with minor perturbations within southwest mid-level flow moves across the area. Modest instability and strong deep-layer shear will support updraft organization and a risk for severe hail and/or damaging gusts. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to move little this afternoon, with low-level moisture advection throughout the warm sector east of this low. Air mass recovery/modification following the overnight MCS is expected, and this will contribute to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises will occur within the large-scale environment. Additionally, warm mid-level temperatures (16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection this afternoon. Isolated thunderstorm development will be possible mainly this evening as a low-level jet strengthens, with a risk for severe wind and isolated hail. ..Bunting.. 06/21/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...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 1140 AM CDT Sat Jun 21 2025 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN GREAT BASIN... Morning satellite imagery shows mainly clear conditions across much of the southwest into southern California, with the exception of a notable marine layer inland across the LA Basin. Surface observations show warming and mixing well underway, with relative humidity in the teens from southern Nevada north into Arizona/Utah and southern Wyoming. Several hours of Critical fire weather conditions are expected within these regions, with winds increasing through the afternoon with the cold front passage and deeper mixing. A small extension was made to the Elevated in New Mexico to account for latest trends with increasing wind speeds amid critical fuels. See previous discussion below for more information concerning Elevated conditions expected in the Central Valley and Santa Barbara Coast in California. ..Thornton.. 06/21/2025 .PREV DISCUSSION... /ISSUED 0122 AM CDT Sat Jun 21 2025/ ...Synopsis... Widespread elevated to critical fire weather conditions are expected again this afternoon across a large swath of the eastern Great Basin and Four Corners region. An upper ridge is evident across the central CONUS in early-morning water-vapor imagery. Across the Pacific Northwest, an upper wave continues to slowly amplify as a low/mid-level cold front pushes southeast into the western Great Basin. A belt of strong southwesterly flow will remain in place across the eastern Great Basin and greater Four Corners region through peak heating ahead of the front. Strong winds within the pre-frontal regime, combined with antecedent dry conditions and receptive fuels, will promote widespread fire weather concerns. ...Southern Nevada into southern Wyoming... Little to no appreciable moisture recovery is expected over the next 12-24 hours across the eastern Great Basin and parts of the Four Corners. The very dry conditions sampled by 00 UTC RAOBs and early-morning surface obs should largely remain in place with another day of RH minimums in the single digits expected. A deep, dry boundary layer will promote efficient downward mixing of the stronger mid-level winds. Similar conditions yesterday (Friday) resulted in widespread sustained winds between 20-25 mph with frequent gusts between 35-50 mph. Similar wind speeds are expected today, albeit within a more confined corridor given the impingement of the cold front from the northwest. Active fires are noted in GOES IR imagery across the region, which indicates that fuels remain very supportive of fire spread. The passage of the cold front later this evening/tonight will result in a wind shift from southwest to northwesterly, which could result in additional fire spread. ...CA Central Valley... Northerly down-valley winds are expected to strengthen to 15-20 mph within the Sacramento/San Joaquin Valley this afternoon within the post-frontal regime. Despite an influx of cooler air, downslope warming/drying should promote areas of 15-20% RH by peak heating. Elevated to locally critical fire weather conditions are expected, and dry grasses within the valley should support the fire concern. ...Santa Barbara Coast... Northerly downslope winds are expected to increase off the Sierra Madre and San Rafael mountains as the cold front passes later this afternoon/tonight. This will promote elevated to locally critical fire weather conditions along the Santa Barbara coast where fuels have sufficiently dried in recent days to support fire spread. ...Central High Plains... 15-25 mph southwesterly winds are expected this afternoon behind a surface trough/dryline. Trajectories emanating off the higher terrain, coupled with ample daytime heating, will promote sufficient drying for RH minimums in the teens. Somewhat widespread elevated to critical fire weather conditions are expected; however, spring green up of grasses and recent rainfall should modulate the overall fire potential. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1396 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHERN LOWER MI
Mesoscale Discussion 1396 NWS Storm Prediction Center Norman OK 0854 AM CDT Sat Jun 21 2025 Areas affected...northern Lower MI Concerning...Severe potential...Watch possible Valid 211354Z - 211530Z Probability of Watch Issuance...40 percent SUMMARY...Isolated large hail and locally strong gusts will remain possible into midday with elevated thunderstorms spreading across the northern Lower Michigan vicinity. DISCUSSION...Within the corridor of strong lower-level warm theta-e advection, a recent uptick in convective intensity has occurred across northern Lake MI and adjacent portions of northern Lower/southern Upper MI. The 12Z APX sounding sampled moderate elevated buoyancy with weakness in the mid-level hodograph. But the upstream GRB sounding sampled substantially stronger mid-level westerlies, which have recently overspread northern Lower MI per the APX VWP data. This will support embedded supercell structures despite convective mode likely to remain dominated by clusters/short-line segments. While the mode should temper overall hail magnitudes to an extent, around golf-ball size hail is possible. Relatively cooler surface temperatures ahead of this activity and the elevated character should also subdue the overall wind damage threat. ..Grams/Bunting.. 06/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...APX... LAT...LON 45758385 45338326 44988325 44858361 44948467 45008541 45048620 45238673 45708612 45938551 45998489 45758385 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Sat Jun 21 2025 Valid 211300Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MICHIGAN AS WELL AS NORTHERN NEW YORK... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from Michigan into the Lower Great Lakes region. Isolated severe storms could also occur across the northern High Plains and Middle Missouri Valley. ...Great Lakes... Outflow and remnant convection from last night's severe MCS over the northern Plains and Upper Midwest is currently moving over Upper MI and northern MI, while the vorticity maximum is moving through far northwestern Ontario. General expectation is for the vorticity maximum to continue eastward through central Ontario and southern Quebec, with some ascent associated with this system glancing the Lower Great Lakes region tonight. The low-level jet is expected to persist, helping to maintain an isolated severe potential with the activity ongoing on the Upper Great Lakes region for the next few hours. There is some chance the reintensification occurs along the outflow later this morning across Lower MI where daytime heating will contribute to strengthening buoyancy. A Slight Risk was maintain for this scenario, although warm low/mid-level temperatures and resultant capping cast doubt to its viability. Farther east across the Lower Great Lakes region, a few late afternoon storms are possible as the convection currently over Lower MI reaches the region. Limited buoyancy should keep any severe threat with these storm isolated. Additionally, as previously mentioned, some ascent should glance the Lower Great Lakes vicinity late tonight/early tomorrow. Forecast soundings depict moderately steep mid-level lapse rates and unidirectional wind profiles supportive of a few strong to severe storms. ...Eastern MT into Western ND... A few elevated storms are currently ongoing across eastern MT, within a region of strong large-scale ascent ahead of an approaching shortwave trough. These isolated storms will likely persist this morning, with a few additional storms possible later this afternoon. Instability will be modest, limited in the overall severe potential, but strong shear will support organization within an updrafts than can mature. Isolated hail and/or damaging gusts are the primary severe risk. ...Central NE/SD/ND into the Upper Midwest... Surface low currently over central SD is expected to drift slowly eastward throughout the day, with notable low-level moisture advection across throughout the warm sector east of this low. This will allow the airmass to recover from the overnight MCS while also contributing to a sharpening warm-frontal zone. Strong to extreme buoyancy (i.e. MLCAPE greater from 3000 to 5000 J/kg) is expected by this evening along this warm front from the ND/SD border vicinity eastward through central MN into northern WI. Some low-level convergence is anticipated in this region, but height rises are anticipated within the large-scale environment. Additionally, warm mid-level temperatures (i.e. 16 to 17 deg C at 700 mb) are expected, capping the airmass to deep convection. Given these factors and the lack of convection within any of the convection-allow guidance, the Marginal Risk was removed from the majority of the region. The only exception was from central NE into southeast SD and far southwest MN where some late night elevated storms capable of hail are possible. ..Mosier/Leitman.. 06/21/2025 Read more

MD 1395 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF LOWER MI
Mesoscale Discussion 1395 NWS Storm Prediction Center Norman OK 0521 AM CDT Sat Jun 21 2025 Areas affected...portions of Lower MI Concerning...Severe potential...Watch unlikely Valid 211021Z - 211145Z Probability of Watch Issuance...20 percent SUMMARY...Isolated convection may occasionally produce hail and gusty winds through early morning. DISCUSSION...Isolated storms will develop/move generally east across portions of northern/central Lower MI the next several hours. This activity is occurring within a moderately unstable and strongly sheared airmass. However, strong low-level inhibition means these storms will likely remain elevated within the warm advection regime on the periphery of the low-level jet. Steep midlevel lapse rates, supercell wind profiles, and modest instability will still foster potential for strong to isolated severe storms produce hail and gusty winds the next few hours. Trends will continue to be monitored, but a watch is not currently expected. ..Leitman/Mosier.. 06/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...APX...GRR... LAT...LON 46038530 45538336 43968350 43478446 43658517 44378616 44708636 45198640 46038530 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more