Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1141 AM CDT Fri Aug 08 2025 Valid 081700Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE FOUR CORNERS INTO SOUTHERN WYOMING... Minor adjustments were made to reduce isolated dry thunderstorm coverage across eastern Arizona and in central Colorado. This change is in agreement with recent trends in HREF guidance, with a decrease in signal (<10%) for thunderstorms across these regions. Otherwise, the Elevated and Critical delineations remain unchanged. See previous discussion below for more info. ..Thornton.. 08/08/2025 .PREV DISCUSSION... /ISSUED 0132 AM CDT Fri Aug 08 2025/ ...Synopsis... Critical fire weather conditions are expected from northern Arizona into eastern UT, western CO, and southern WY this afternoon. Early-morning surface observations show southwesterly flow advecting hot/dry air out of the Mohave Desert and into the eastern Great Basin/Four Corners region. This will support another day of sub-10% RH minimums from northern AZ into UT and western CO. Aloft, the passage of a mid-level trough axis will support strengthening flow over the Intermountain West as well as lee troughing across the central High Plains. The result will be bolstered low-level flow across the Four Corners/central Rockies with most guidance suggesting that sustained winds between 20-25 mph are likely. Deep mixing through peak heating will promote frequent wind gusts between 30-45 mph, especially across south-central to eastern UT where ensemble guidance shows the strongest wind signal. Recent reports of active ongoing fires across UT/CO confirm that receptive fuels are in place and will support the Critical fire weather threat. ...Dry Thunderstorms... Lift ahead of the passing trough axis will impinge on the northeastern fringe of a modest plume of recycled monsoonal moisture and support isolated thunderstorm development by late afternoon from eastern AZ to southern CO. 00z RAOBs from across the Southwest sampled steep mid-level lapse rates, deep/dry boundary layers, and PWAT values on the order of 0.5 to 0.8 inches, which are all favorable for dry thunderstorms. While storm coverage is expected to be sparse, thunderstorms that do develop may pose a dry lightning threat over a region with 10-hour fuel moisture near 10% and ongoing moderate to severe drought. ...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 1141 AM CDT Fri Aug 08 2025 Valid 081700Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE FOUR CORNERS INTO SOUTHERN WYOMING... Minor adjustments were made to reduce isolated dry thunderstorm coverage across eastern Arizona and in central Colorado. This change is in agreement with recent trends in HREF guidance, with a decrease in signal (<10%) for thunderstorms across these regions. Otherwise, the Elevated and Critical delineations remain unchanged. See previous discussion below for more info. ..Thornton.. 08/08/2025 .PREV DISCUSSION... /ISSUED 0132 AM CDT Fri Aug 08 2025/ ...Synopsis... Critical fire weather conditions are expected from northern Arizona into eastern UT, western CO, and southern WY this afternoon. Early-morning surface observations show southwesterly flow advecting hot/dry air out of the Mohave Desert and into the eastern Great Basin/Four Corners region. This will support another day of sub-10% RH minimums from northern AZ into UT and western CO. Aloft, the passage of a mid-level trough axis will support strengthening flow over the Intermountain West as well as lee troughing across the central High Plains. The result will be bolstered low-level flow across the Four Corners/central Rockies with most guidance suggesting that sustained winds between 20-25 mph are likely. Deep mixing through peak heating will promote frequent wind gusts between 30-45 mph, especially across south-central to eastern UT where ensemble guidance shows the strongest wind signal. Recent reports of active ongoing fires across UT/CO confirm that receptive fuels are in place and will support the Critical fire weather threat. ...Dry Thunderstorms... Lift ahead of the passing trough axis will impinge on the northeastern fringe of a modest plume of recycled monsoonal moisture and support isolated thunderstorm development by late afternoon from eastern AZ to southern CO. 00z RAOBs from across the Southwest sampled steep mid-level lapse rates, deep/dry boundary layers, and PWAT values on the order of 0.5 to 0.8 inches, which are all favorable for dry thunderstorms. While storm coverage is expected to be sparse, thunderstorms that do develop may pose a dry lightning threat over a region with 10-hour fuel moisture near 10% and ongoing moderate to severe drought. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Fri Aug 08 2025 Valid 081630Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT OVER PARTS THE UPPER MIDWEST.... ...SUMMARY... Scattered severe thunderstorms are possible this evening and tonight across parts of the Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Upper Midwest... The large convective complex that affected ND/MN last night has mostly dissipated, with the associated shortwave trough lifting across the MN Arrowhead. Shortwave ridging is occurring in the wake of this system, which should suppress deep convective development for most of the afternoon. Southeasterly low-level winds and daytime heating across much of MN and eastern SD will help re-establish a very moist/unstable air mass (MLCAPE > 4000 J/kg) by late afternoon. Another strong shortwave trough now over WY will begin affecting the ND/MN area by that time, with an associated cold front approaching the area. Scattered thunderstorms are expected to form along/ahead of the front, mainly after 00z. Deep-layer shear will support supercell storm structures capable of large hail and damaging wind gusts. A few tornadoes are also possible, given the very moist environment and backed low-level winds. However, many of the storms may be elevated and behind the front. Activity will persist deep into the night, spreading eastward across MN and into parts of northern WI and western Upper MI. ..Hart/Squitieri.. 08/08/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Fri Aug 08 2025 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE EASTERN DAKOTAS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible later today and tonight across parts of the northern Plains and Upper Midwest. Scattered damaging winds, large hail, and a couple tornadoes are possible. ...Northern Plains into the Upper Mississippi Valley... An extensive MCS which produced numerous severe wind gusts across ND earlier this morning has recently weakened across northern MN. While occasional strong to locally damaging gusts may still occur in the short term, this convection should continue weakening through the rest of the morning as it moves into a less favorable thermodynamic environment. In the wake of this activity, an upper trough/low will continue advancing eastward across the northern Rockies/Plains towards the Upper Midwest through the period. At the surface, a weak low over central SD this morning should develop northeastward to northern MN by this evening, while a trailing cold front advances southward across the northern/central High Plains. Outflow from the morning convection may act as a pseudo warm front and focus for renewed intense thunderstorm development later today across parts of central/northern MN. The southern extent and location of this boundary by this evening remains somewhat uncertain. Even so, a rather moist and strongly to extremely unstable airmass will be present east of the cold front and south of the outflow boundary by late this afternoon across the upper MS Valley. It still appears probable that additional surface-based convection may develop by late afternoon/early evening across eastern ND/northwest MN and vicinity as large-scale ascent preceding the upper trough/low overspreads the warm sector. While stronger flow aloft may tend to lag the surface cold front to some extent, there should still be sufficient deep-layer shear to support organized updrafts, including supercells with some large hail threat. Given a large degree of boundary-parallel flow aloft, a quick linear transition should occur this evening, with a greater threat for severe/damaging winds. A narrow window for a couple of tornadoes may exist across parts of MN, mainly this evening along/near the residual outflow boundary where effective SRH may become locally enhanced with a gradual strengthening of a southerly low-level jet. Otherwise, the threat for damaging winds may continue through tonight across parts of the upper MS Valley so long as any MCS that develops can remain surface based. Given the potential effects of the ongoing morning convection, confidence in a corridor of more concentrated wind potential remains too low to include greater severe probabilities with this update. ...High Plains... Thunderstorms are ongoing this morning along/north of a cold front in the western Dakotas. This activity may pose an isolated hail threat given ample MUCAPE and strong deep-layer shear. The potential for additional thunderstorms this afternoon/evening across the central High Plains either along or behind the front in a low-level upslope flow regime remains unclear. A conditional risk for supercells with associated large hail threat is still apparent, but overall coverage of intense convection may remain quite isolated. Farther south across the southern High Plains, high-based convection is expected to develop this afternoon within a hot and well-mixed boundary layer. Deep-layer flow and related shear will generally remain weak, but outflow-driven clusters may still be capable of localized severe gusts. ...Northern Lower Michigan... Similar to yesterday, isolated strong to severe thunderstorms may develop this afternoon and evening across parts of northern Lower MI and vicinity, along the northeast periphery of the substantial reservoir of instability over the central Plains and Midwest. Modest northwesterly flow aloft will provide sufficient shear for some updraft organization, with a threat for occasional hail and damaging winds. ..Gleason/Leitman.. 08/08/2025 Read more

WW 0577 Status Updates
STATUS REPORT ON WW 577 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 WNW AXN TO 25 NNE DTL TO 30 ESE TVF TO 25 NNE TVF TO 20 NNE HCO. ..LEITMAN..08/08/25 ATTN...WFO...FGF...BIS... STATUS REPORT FOR WS 577 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-007-029-057-077-111-135-159-081240- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER BELTRAMI CLEARWATER HUBBARD LAKE OF THE WOODS OTTER TAIL ROSEAU WADENA THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 577 SEVERE TSTM MN ND 080455Z - 081200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 577 NWS Storm Prediction Center Norman OK 1155 PM CDT Thu Aug 7 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest Minnesota Eastern and Southern North Dakota * Effective this Thursday night and Friday morning from 1155 PM until 700 AM CDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 80 mph possible Isolated very large hail events to 2 inches in diameter possible A tornado or two possible SUMMARY...Multiple bowing linear clusters of storms will continue generally eastward overnight with potentially widespread wind damage, occasional hail, and perhaps some line-embedded tornado risk. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 20 miles northeast of Hallock MN to 65 miles south of Jamestown ND. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 576... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 26035. ...Guyer Read more

WW 0577 Status Updates
STATUS REPORT ON WW 577 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NNE ABR TO 25 WSW FAR TO 10 S GFK TO 50 WSW HCO TO 45 NW HCO. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1903. ..LEITMAN..08/08/25 ATTN...WFO...FGF...BIS... STATUS REPORT FOR WS 577 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-027-029-069-087-089-107-111-113-119-125-135-167-081040- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER CLAY CLEARWATER KITTSON MAHNOMEN MARSHALL NORMAN OTTER TAIL PENNINGTON POLK RED LAKE ROSEAU WILKIN NDC017-035-067-073-077-081-097-099-081040- ND . NORTH DAKOTA COUNTIES INCLUDED ARE CASS GRAND FORKS PEMBINA RANSOM RICHLAND SARGENT TRAILL WALSH THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE Read more

MD 1903 CONCERNING SEVERE THUNDERSTORM WATCH 577... FOR FAR EASTERN ND INTO NORTHWEST MN
Mesoscale Discussion 1903 NWS Storm Prediction Center Norman OK 0431 AM CDT Fri Aug 08 2025 Areas affected...far eastern ND into northwest MN Concerning...Severe Thunderstorm Watch 577... Valid 080931Z - 081100Z The severe weather threat for Severe Thunderstorm Watch 577 continues. SUMMARY...Strong to severe wind gusts remain possible the next couple hours across northwest Minnesota. A gradual weakening trend is expected through early morning with south and east extent across northeast/central Minnesota. DISCUSSION...A well organized bow echo moving out of eastern ND into northwest MN has produced gusts in the 55-80 kt range over the past 1-2 hours, and perhaps a brief tornado west of Grand Forks within leading-edge mesovortices. The VWP from KMVX shows a strong rear-inflow signature of 70-80 kt in the 1-2 km range. Severe gusts will likely persist another couple of hours into northwest MN given the well-organized nature of the bow echo and a favorable CAPE/shear downstream environment. With south and eastward extent, instability decreases and increasing inhibition should result in a gradual weakening trend into central and northeast MN through early morning. A local expansion of WW 577 may be needed across northwest MN/the remainder of the Grand Forks CWA. However, the need for a downstream watch is uncertain and will depend on convective trends over the next hour or so. ..Leitman.. 08/08/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...MPX...FGF...ABR...BIS... LAT...LON 49079676 49119547 49069466 48609406 47809364 47089367 46419419 45869528 45649644 45929804 46539786 48069793 48879796 49079676 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

WW 0577 Status Updates
STATUS REPORT ON WW 577 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ENE MBG TO 25 SE JMS TO 35 NNE JMS TO 65 WNW HCO. ..LEITMAN..08/08/25 ATTN...WFO...FGF...BIS... STATUS REPORT FOR WS 577 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-027-029-069-087-089-107-111-113-119-125-135-167-080940- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER CLAY CLEARWATER KITTSON MAHNOMEN MARSHALL NORMAN OTTER TAIL PENNINGTON POLK RED LAKE ROSEAU WILKIN NDC003-017-021-035-039-045-051-063-067-073-077-081-091-097-099- 080940- ND . NORTH DAKOTA COUNTIES INCLUDED ARE BARNES CASS DICKEY GRAND FORKS GRIGGS LAMOURE MCINTOSH NELSON PEMBINA RANSOM RICHLAND SARGENT STEELE TRAILL WALSH Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0322 AM CDT Fri Aug 08 2025 Valid 111200Z - 161200Z ...DISCUSSION... A weak upper trough over the north-central U.S. on Monday/D4 will move into the upper Great Lakes on Tuesday/D5, then eject into eastern Canada by Wednesday/D6. From D6 through Friday/D8, another wave is forecast to develop over the Pacific Northwest, and move across the northern Rockies. At the surface, a moist air mass will remain over much of the central and eastern states, with minimal surface focus. However, daily areas of thunderstorms, some with gusty winds, are likely to occur from the upper Great Lakes to the southern Plains for Monday/D4 into Tuesday/D5, and then into the OH/TN Valleys and Northeast thereafter. Perhaps by D7/D8, the northern Rockies trough will interact with stronger instability over the northern Plains with a wind or hail threat, but predictability is low this far out for such a minimal system. Read more