Severe Storms

MD 1904 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL TO NORTHEAST LOWER MICHIGAN
Mesoscale Discussion 1904 NWS Storm Prediction Center Norman OK 0533 PM CDT Fri Aug 08 2025 Areas affected...Central to northeast Lower Michigan Concerning...Severe potential...Watch unlikely Valid 082233Z - 090000Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms will continue to develop across Lower Michigan for the next couple of hours, and may pose a transient severe hail/wind threat. Watch issuance is not expected. DISCUSSION...Transient convection has been ongoing across Lower MI along a surface confluence zone for the past couple of hours, but a couple of deeper cells have developed across northeast Lower MI over the past 30-60 minutes per IR imagery and composite reflectivity. Based on MRMS vertical ice data, these cells likely reached sufficient intensity for isolated severe hail (most likely 1 to 1.25 inch in diameter) before gradually weakening. Continued low-level ascent within a weakly capped and buoyant (2000 J/kg MLCAPE) environment will likely continue to promote isolated thunderstorm development prior to sunset and the onset of nocturnal cooling. However, modest deep-layer shear (per regional VWPs) will promote transient storm organization and the potential for sporadic severe hail and damaging winds. In general, the severe threat is expected to remain sufficiently limited to preclude watch issuance. ..Moore/Guyer.. 08/08/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...APX...GRR... LAT...LON 43208427 43148459 43218494 43348516 43588530 43898533 44148508 44468477 44808460 45258420 45398388 45448358 45328334 45048316 44678308 44068316 43708344 43458378 43208427 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

No Mesoscale Discussions are in effect as of Fri Aug 8 22:27:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0327 PM CDT Fri Aug 08 2025 Valid 101200Z - 161200Z An upper-level ridge over the Southwest will shift westward and build across much of the West by D4/Monday. An upper-level trough will eject across the Pacific Northwest D5/Tuesday into D6/Wednesday, bringing an increase to winds amid dry conditions. Monsoonal moisture may return northward across portions of Arizona late in the extended, with possible expansion of dry thunderstorm chances. ...Dry Thunderstorms... Residual moisture beneath the ridge should allow for a continuation of afternoon thunderstorm potential on D3/Sunday for portions of the Southwest amid low environmental PWAT values and receptive fuels. 10% probabilities have been maintained for the region through Sunday. Thunderstorm potential may extend into early next week, with a gradual increase in moisture northward. Limited predictability within the weak-flow regime beyond D3/Sunday precludes introducing any additional highlights. ...Wind/RH... Elevated to critical conditions may arise next week (D5/Tuesday-D7/Thursday) for portions of the Pacific Northwest and northern Great Basin, as a trough moves inland and enhanced westerly flow overspreads the region. However, considerable spread exists among medium-range guidance regarding the timing/placement/magnitude of this trough, precluding the introduction of any highlights at this time. ..Thornton.. 08/08/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Fri Aug 08 2025 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO TONIGHT FOR PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds, large hail, and a couple tornadoes are possible this evening and tonight across parts of the Upper Midwest and the central High Plains. ...20z Update... ...Upper Midwest... Latest radar/satellite trends show a residual storm complex and cloud cover over northeast Minnesota. This activity continues to diminish, with some weak convection developing in proximity. Surface observations suggest little evidence of extensive outflow in its wake, though southeasterly surface winds are prevalent across much of Minnesota where cloud cover has remained persistent. To the west, a cold front continues to advance eastward and is beginning to impinge upon portions of northwest Minnesota into eastern South Dakota. Storm initiation is still expected by early evening along the cold front in eastern South/North Dakota, with a quick transition from cellular to linear modes. Not much has changed in terms of expectations from the prior outlook. As this activity grows upscale and matures, some potential for a more concentrated corridor of damaging winds may emerge in far northeast Minnesota, but details remain uncertain and will be reevaluated in the 01z Outlook. With that said, given the potential for upscale growth, have expanded the Marginal area (Level 1 of 5) eastward into portions of northeast Iowa and vicinity. ...Southwest South Dakota/Nebraska Panhandle... Surface observations and SPC mesoanalysis show a post-frontal airmass with enough residual moisture to allow for modest destabilization across the region. Recent CAM guidance suggests the potential for isolated convection to develop in the high terrain of eastern Wyoming and persist eastward into southwest South Dakota and the Nebraska Panhandle. Given effective shear of 45-50 kt in association with enhanced flow along the southern periphery of the upper-level trough, a few supercell storms are possible with severe hail/wind the main threats. Therefore, have introduced a Slight Risk (Level 2 of 5) to encompass this potential. ..Karstens/Lyons.. 08/08/2025 .PREV DISCUSSION... /ISSUED 1118 AM CDT Fri Aug 08 2025/ ...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. Read more