Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Within the base of a robust midlevel trough moving across the northern Rockies, a belt of enhanced deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies -- to the north of an expansive midlevel anticyclone centered over the southern Rockies. ...Great Basin into the Central Rockies... Diurnal heating will yield deep boundary-layer mixing into the enhanced flow aloft across the Great Basin into the central Rockies. As a result, widespread single-digit to lower teens RH will develop amid 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry/receptive fuels, another day of critical fire-weather conditions are expected. ...Dry Thunderstorms - Southwest into the Central Rockies... Within a plume of midlevel moisture extending from the Southwest into the central Rockies, diurnally driven high-based thunderstorms are expected -- with a focus over the higher terrain. These storms will be mostly dry, owing to inverted-V soundings (0.50 to 0.70 inch PW) -- posing a risk of lightning-induced ignitions and strong outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Within the base of a robust midlevel trough moving across the northern Rockies, a belt of enhanced deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies -- to the north of an expansive midlevel anticyclone centered over the southern Rockies. ...Great Basin into the Central Rockies... Diurnal heating will yield deep boundary-layer mixing into the enhanced flow aloft across the Great Basin into the central Rockies. As a result, widespread single-digit to lower teens RH will develop amid 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry/receptive fuels, another day of critical fire-weather conditions are expected. ...Dry Thunderstorms - Southwest into the Central Rockies... Within a plume of midlevel moisture extending from the Southwest into the central Rockies, diurnally driven high-based thunderstorms are expected -- with a focus over the higher terrain. These storms will be mostly dry, owing to inverted-V soundings (0.50 to 0.70 inch PW) -- posing a risk of lightning-induced ignitions and strong outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0109 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected Friday afternoon and evening across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A negatively tilted mid-level trough and an associated 50 to 60 knot jet streak will move through the northern Plains on Friday. At the surface, a cold front will advance eastward across the Dakotas, as convection early in the day moves through the upper Mississippi Valley. Ahead of the front, a moist and strongly unstable airmass will be in place, with surface dewpoints from the upper 60s to the mid 70s F. Low-level convergence will increase ahead of the front in the afternoon, helping to support scattered thunderstorm development. A cluster of strong to severe storms appears likely across parts of the northern Plains Friday afternoon and evening. A pristine thermodynamic environment is forecast to develop across the northern Plains Friday afternoon. NAM forecast soundings in the late afternoon along the instability axis near Fargo, North Dakota have MLCAPE near 5,500 J/kg with 700-500 mb lapse rates approaching 8.5 C/km. Along the axis of instability, 0-6 km shear is forecast to be in the 35 to 45 knot range, which should be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible within the stronger cores. Severe wind gusts will also be possible. There is some concern that convection along or ahead of the front will remain to the west of the strongest instability. Although the models vary concerning this scenario, the latest ECMWF has trended toward an earlier convective initiation. The ECMWF solution, which also develops convection further to the south, would be more favorable for a significant severe weather event across the northern Plains Friday afternoon and evening. ...Western Dakotas... A post-frontal airmass will be in place across the western Dakotas on Friday, as a cold front advances eastward away from the region. Warming surface temperatures will contribute to weak instability by afternoon, with MLCAPE approaching 1000 J/kg in some areas. Large-scale ascent associated with a mid-level shortwave trough should aid the development of a few thunderstorms during the late afternoon and early evening. Moderate deep-layer shear and steep mid-level lapse rates could be enough for a localized severe threat, with hail and isolated severe wind gusts possible. ..Broyles.. 08/07/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0109 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected Friday afternoon and evening across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A negatively tilted mid-level trough and an associated 50 to 60 knot jet streak will move through the northern Plains on Friday. At the surface, a cold front will advance eastward across the Dakotas, as convection early in the day moves through the upper Mississippi Valley. Ahead of the front, a moist and strongly unstable airmass will be in place, with surface dewpoints from the upper 60s to the mid 70s F. Low-level convergence will increase ahead of the front in the afternoon, helping to support scattered thunderstorm development. A cluster of strong to severe storms appears likely across parts of the northern Plains Friday afternoon and evening. A pristine thermodynamic environment is forecast to develop across the northern Plains Friday afternoon. NAM forecast soundings in the late afternoon along the instability axis near Fargo, North Dakota have MLCAPE near 5,500 J/kg with 700-500 mb lapse rates approaching 8.5 C/km. Along the axis of instability, 0-6 km shear is forecast to be in the 35 to 45 knot range, which should be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible within the stronger cores. Severe wind gusts will also be possible. There is some concern that convection along or ahead of the front will remain to the west of the strongest instability. Although the models vary concerning this scenario, the latest ECMWF has trended toward an earlier convective initiation. The ECMWF solution, which also develops convection further to the south, would be more favorable for a significant severe weather event across the northern Plains Friday afternoon and evening. ...Western Dakotas... A post-frontal airmass will be in place across the western Dakotas on Friday, as a cold front advances eastward away from the region. Warming surface temperatures will contribute to weak instability by afternoon, with MLCAPE approaching 1000 J/kg in some areas. Large-scale ascent associated with a mid-level shortwave trough should aid the development of a few thunderstorms during the late afternoon and early evening. Moderate deep-layer shear and steep mid-level lapse rates could be enough for a localized severe threat, with hail and isolated severe wind gusts possible. ..Broyles.. 08/07/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0109 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected Friday afternoon and evening across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A negatively tilted mid-level trough and an associated 50 to 60 knot jet streak will move through the northern Plains on Friday. At the surface, a cold front will advance eastward across the Dakotas, as convection early in the day moves through the upper Mississippi Valley. Ahead of the front, a moist and strongly unstable airmass will be in place, with surface dewpoints from the upper 60s to the mid 70s F. Low-level convergence will increase ahead of the front in the afternoon, helping to support scattered thunderstorm development. A cluster of strong to severe storms appears likely across parts of the northern Plains Friday afternoon and evening. A pristine thermodynamic environment is forecast to develop across the northern Plains Friday afternoon. NAM forecast soundings in the late afternoon along the instability axis near Fargo, North Dakota have MLCAPE near 5,500 J/kg with 700-500 mb lapse rates approaching 8.5 C/km. Along the axis of instability, 0-6 km shear is forecast to be in the 35 to 45 knot range, which should be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible within the stronger cores. Severe wind gusts will also be possible. There is some concern that convection along or ahead of the front will remain to the west of the strongest instability. Although the models vary concerning this scenario, the latest ECMWF has trended toward an earlier convective initiation. The ECMWF solution, which also develops convection further to the south, would be more favorable for a significant severe weather event across the northern Plains Friday afternoon and evening. ...Western Dakotas... A post-frontal airmass will be in place across the western Dakotas on Friday, as a cold front advances eastward away from the region. Warming surface temperatures will contribute to weak instability by afternoon, with MLCAPE approaching 1000 J/kg in some areas. Large-scale ascent associated with a mid-level shortwave trough should aid the development of a few thunderstorms during the late afternoon and early evening. Moderate deep-layer shear and steep mid-level lapse rates could be enough for a localized severe threat, with hail and isolated severe wind gusts possible. ..Broyles.. 08/07/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0109 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected Friday afternoon and evening across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A negatively tilted mid-level trough and an associated 50 to 60 knot jet streak will move through the northern Plains on Friday. At the surface, a cold front will advance eastward across the Dakotas, as convection early in the day moves through the upper Mississippi Valley. Ahead of the front, a moist and strongly unstable airmass will be in place, with surface dewpoints from the upper 60s to the mid 70s F. Low-level convergence will increase ahead of the front in the afternoon, helping to support scattered thunderstorm development. A cluster of strong to severe storms appears likely across parts of the northern Plains Friday afternoon and evening. A pristine thermodynamic environment is forecast to develop across the northern Plains Friday afternoon. NAM forecast soundings in the late afternoon along the instability axis near Fargo, North Dakota have MLCAPE near 5,500 J/kg with 700-500 mb lapse rates approaching 8.5 C/km. Along the axis of instability, 0-6 km shear is forecast to be in the 35 to 45 knot range, which should be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible within the stronger cores. Severe wind gusts will also be possible. There is some concern that convection along or ahead of the front will remain to the west of the strongest instability. Although the models vary concerning this scenario, the latest ECMWF has trended toward an earlier convective initiation. The ECMWF solution, which also develops convection further to the south, would be more favorable for a significant severe weather event across the northern Plains Friday afternoon and evening. ...Western Dakotas... A post-frontal airmass will be in place across the western Dakotas on Friday, as a cold front advances eastward away from the region. Warming surface temperatures will contribute to weak instability by afternoon, with MLCAPE approaching 1000 J/kg in some areas. Large-scale ascent associated with a mid-level shortwave trough should aid the development of a few thunderstorms during the late afternoon and early evening. Moderate deep-layer shear and steep mid-level lapse rates could be enough for a localized severe threat, with hail and isolated severe wind gusts possible. ..Broyles.. 08/07/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0109 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected Friday afternoon and evening across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A negatively tilted mid-level trough and an associated 50 to 60 knot jet streak will move through the northern Plains on Friday. At the surface, a cold front will advance eastward across the Dakotas, as convection early in the day moves through the upper Mississippi Valley. Ahead of the front, a moist and strongly unstable airmass will be in place, with surface dewpoints from the upper 60s to the mid 70s F. Low-level convergence will increase ahead of the front in the afternoon, helping to support scattered thunderstorm development. A cluster of strong to severe storms appears likely across parts of the northern Plains Friday afternoon and evening. A pristine thermodynamic environment is forecast to develop across the northern Plains Friday afternoon. NAM forecast soundings in the late afternoon along the instability axis near Fargo, North Dakota have MLCAPE near 5,500 J/kg with 700-500 mb lapse rates approaching 8.5 C/km. Along the axis of instability, 0-6 km shear is forecast to be in the 35 to 45 knot range, which should be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible within the stronger cores. Severe wind gusts will also be possible. There is some concern that convection along or ahead of the front will remain to the west of the strongest instability. Although the models vary concerning this scenario, the latest ECMWF has trended toward an earlier convective initiation. The ECMWF solution, which also develops convection further to the south, would be more favorable for a significant severe weather event across the northern Plains Friday afternoon and evening. ...Western Dakotas... A post-frontal airmass will be in place across the western Dakotas on Friday, as a cold front advances eastward away from the region. Warming surface temperatures will contribute to weak instability by afternoon, with MLCAPE approaching 1000 J/kg in some areas. Large-scale ascent associated with a mid-level shortwave trough should aid the development of a few thunderstorms during the late afternoon and early evening. Moderate deep-layer shear and steep mid-level lapse rates could be enough for a localized severe threat, with hail and isolated severe wind gusts possible. ..Broyles.. 08/07/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NORTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are expected later today into tonight. The most likely corridor is centered on North Dakota, where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Significant severe storms capable of producing wind gusts of 75+ mph, very large hail, and possibly a few tornadoes are still expected in an area centered on ND later today into tonight. A mid/upper-level trough is forecast to amplify over parts of the Northwest/northern Rockies today as it moves eastward. One or more low-amplitude vorticity maxima may precede the larger-scale trough and move across the northern Great Plains during the afternoon and evening. A surface low is forecast to gradually deepen across the northern High Plains. Rich low-level moisture beneath steep midlevel lapse rates will result in strong to extreme buoyancy within the warm sector of this cyclone, and also near/north of a baroclinic zone that will extend east/northeast of the low. This instability combined with moderate deep-layer shear will result in a very favorable conditional environment for severe storms. Guidance generally depicts one or more intense storm clusters moving across ND sometime later today into tonight, but considerable spread remains regarding timing of the primary threat, and the duration and coverage of supercells. There is some potential for morning elevated convection to become increasingly organized with time, with renewed development during the afternoon possible near the surface low and baroclinic zone. Any supercells within this regime would pose a threat of very large hail, along with some tornado potential, especially near the baroclinic zone. A tendency toward clustering and MCS development is expected with time, increasing the threat for one or more swaths of significant severe wind, along with some potential for line-embedded tornadoes. The southern and eastern extent of higher-end severe potential remains uncertain, due to differences regarding storm timing and the position of the main baroclinic zone. Farther west, isolated to widely scattered supercells may develop within a moderately unstable post-frontal regime from central into eastern MT. Elongated hodographs and steep lapse rates will support severe hail and wind potential with these cells. Some clustering remains possible within this regime as well, and depending on the evolution of downstream convection, storms that initiate in MT may eventually spread into western/central ND late tonight with a continued severe threat. ...IL/eastern IA into WI and western upper MI... Some potential for strong to locally severe storms remains evident within a broad area from IL/eastern IA into WI and western upper MI, though uncertainty remains regarding the potential for a more organized threat somewhere within this broader area. Guidance varies regarding the evolution of morning convection across parts of IA/MO, and whether a well-defined MCV will emerge from this area. However, even a weak MCV or other low-amplitude vorticity maxima may aid in scattered to widespread storm development late this afternoon into the evening, within a modest low-level warm advection regime. Deep-layer flow will be relatively modest, but rich moisture and moderate to strong buoyancy will support a threat for at least isolated hail and damaging wind. ..Dean/Weinman.. 08/07/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NORTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are expected later today into tonight. The most likely corridor is centered on North Dakota, where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Significant severe storms capable of producing wind gusts of 75+ mph, very large hail, and possibly a few tornadoes are still expected in an area centered on ND later today into tonight. A mid/upper-level trough is forecast to amplify over parts of the Northwest/northern Rockies today as it moves eastward. One or more low-amplitude vorticity maxima may precede the larger-scale trough and move across the northern Great Plains during the afternoon and evening. A surface low is forecast to gradually deepen across the northern High Plains. Rich low-level moisture beneath steep midlevel lapse rates will result in strong to extreme buoyancy within the warm sector of this cyclone, and also near/north of a baroclinic zone that will extend east/northeast of the low. This instability combined with moderate deep-layer shear will result in a very favorable conditional environment for severe storms. Guidance generally depicts one or more intense storm clusters moving across ND sometime later today into tonight, but considerable spread remains regarding timing of the primary threat, and the duration and coverage of supercells. There is some potential for morning elevated convection to become increasingly organized with time, with renewed development during the afternoon possible near the surface low and baroclinic zone. Any supercells within this regime would pose a threat of very large hail, along with some tornado potential, especially near the baroclinic zone. A tendency toward clustering and MCS development is expected with time, increasing the threat for one or more swaths of significant severe wind, along with some potential for line-embedded tornadoes. The southern and eastern extent of higher-end severe potential remains uncertain, due to differences regarding storm timing and the position of the main baroclinic zone. Farther west, isolated to widely scattered supercells may develop within a moderately unstable post-frontal regime from central into eastern MT. Elongated hodographs and steep lapse rates will support severe hail and wind potential with these cells. Some clustering remains possible within this regime as well, and depending on the evolution of downstream convection, storms that initiate in MT may eventually spread into western/central ND late tonight with a continued severe threat. ...IL/eastern IA into WI and western upper MI... Some potential for strong to locally severe storms remains evident within a broad area from IL/eastern IA into WI and western upper MI, though uncertainty remains regarding the potential for a more organized threat somewhere within this broader area. Guidance varies regarding the evolution of morning convection across parts of IA/MO, and whether a well-defined MCV will emerge from this area. However, even a weak MCV or other low-amplitude vorticity maxima may aid in scattered to widespread storm development late this afternoon into the evening, within a modest low-level warm advection regime. Deep-layer flow will be relatively modest, but rich moisture and moderate to strong buoyancy will support a threat for at least isolated hail and damaging wind. ..Dean/Weinman.. 08/07/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NORTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are expected later today into tonight. The most likely corridor is centered on North Dakota, where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Significant severe storms capable of producing wind gusts of 75+ mph, very large hail, and possibly a few tornadoes are still expected in an area centered on ND later today into tonight. A mid/upper-level trough is forecast to amplify over parts of the Northwest/northern Rockies today as it moves eastward. One or more low-amplitude vorticity maxima may precede the larger-scale trough and move across the northern Great Plains during the afternoon and evening. A surface low is forecast to gradually deepen across the northern High Plains. Rich low-level moisture beneath steep midlevel lapse rates will result in strong to extreme buoyancy within the warm sector of this cyclone, and also near/north of a baroclinic zone that will extend east/northeast of the low. This instability combined with moderate deep-layer shear will result in a very favorable conditional environment for severe storms. Guidance generally depicts one or more intense storm clusters moving across ND sometime later today into tonight, but considerable spread remains regarding timing of the primary threat, and the duration and coverage of supercells. There is some potential for morning elevated convection to become increasingly organized with time, with renewed development during the afternoon possible near the surface low and baroclinic zone. Any supercells within this regime would pose a threat of very large hail, along with some tornado potential, especially near the baroclinic zone. A tendency toward clustering and MCS development is expected with time, increasing the threat for one or more swaths of significant severe wind, along with some potential for line-embedded tornadoes. The southern and eastern extent of higher-end severe potential remains uncertain, due to differences regarding storm timing and the position of the main baroclinic zone. Farther west, isolated to widely scattered supercells may develop within a moderately unstable post-frontal regime from central into eastern MT. Elongated hodographs and steep lapse rates will support severe hail and wind potential with these cells. Some clustering remains possible within this regime as well, and depending on the evolution of downstream convection, storms that initiate in MT may eventually spread into western/central ND late tonight with a continued severe threat. ...IL/eastern IA into WI and western upper MI... Some potential for strong to locally severe storms remains evident within a broad area from IL/eastern IA into WI and western upper MI, though uncertainty remains regarding the potential for a more organized threat somewhere within this broader area. Guidance varies regarding the evolution of morning convection across parts of IA/MO, and whether a well-defined MCV will emerge from this area. However, even a weak MCV or other low-amplitude vorticity maxima may aid in scattered to widespread storm development late this afternoon into the evening, within a modest low-level warm advection regime. Deep-layer flow will be relatively modest, but rich moisture and moderate to strong buoyancy will support a threat for at least isolated hail and damaging wind. ..Dean/Weinman.. 08/07/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu Aug 07 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF NORTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are expected later today into tonight. The most likely corridor is centered on North Dakota, where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Significant severe storms capable of producing wind gusts of 75+ mph, very large hail, and possibly a few tornadoes are still expected in an area centered on ND later today into tonight. A mid/upper-level trough is forecast to amplify over parts of the Northwest/northern Rockies today as it moves eastward. One or more low-amplitude vorticity maxima may precede the larger-scale trough and move across the northern Great Plains during the afternoon and evening. A surface low is forecast to gradually deepen across the northern High Plains. Rich low-level moisture beneath steep midlevel lapse rates will result in strong to extreme buoyancy within the warm sector of this cyclone, and also near/north of a baroclinic zone that will extend east/northeast of the low. This instability combined with moderate deep-layer shear will result in a very favorable conditional environment for severe storms. Guidance generally depicts one or more intense storm clusters moving across ND sometime later today into tonight, but considerable spread remains regarding timing of the primary threat, and the duration and coverage of supercells. There is some potential for morning elevated convection to become increasingly organized with time, with renewed development during the afternoon possible near the surface low and baroclinic zone. Any supercells within this regime would pose a threat of very large hail, along with some tornado potential, especially near the baroclinic zone. A tendency toward clustering and MCS development is expected with time, increasing the threat for one or more swaths of significant severe wind, along with some potential for line-embedded tornadoes. The southern and eastern extent of higher-end severe potential remains uncertain, due to differences regarding storm timing and the position of the main baroclinic zone. Farther west, isolated to widely scattered supercells may develop within a moderately unstable post-frontal regime from central into eastern MT. Elongated hodographs and steep lapse rates will support severe hail and wind potential with these cells. Some clustering remains possible within this regime as well, and depending on the evolution of downstream convection, storms that initiate in MT may eventually spread into western/central ND late tonight with a continued severe threat. ...IL/eastern IA into WI and western upper MI... Some potential for strong to locally severe storms remains evident within a broad area from IL/eastern IA into WI and western upper MI, though uncertainty remains regarding the potential for a more organized threat somewhere within this broader area. Guidance varies regarding the evolution of morning convection across parts of IA/MO, and whether a well-defined MCV will emerge from this area. However, even a weak MCV or other low-amplitude vorticity maxima may aid in scattered to widespread storm development late this afternoon into the evening, within a modest low-level warm advection regime. Deep-layer flow will be relatively modest, but rich moisture and moderate to strong buoyancy will support a threat for at least isolated hail and damaging wind. ..Dean/Weinman.. 08/07/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Wed Aug 06 2025 Valid 070100Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN/CENTRAL PLAINS AND MIDWEST...AND ALSO FOR NORTHWEST MN... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota, this evening into late tonight. ...Eastern WY/southeast MT into western/central SD/northwest NE... A favorable conditional environment remains in place this evening from eastern WY/far southeast MT into western SD/northwest NE, with moderate to strong buoyancy and effective shear of 40-50 kt. However, large-scale ascent is generally weak, and storms that developed across far eastern WY have been very isolated and relatively slow to intensify. A severe storm or two remains possible through the evening, with a threat of isolated hail and localized strong to severe gusts. Isolated strong to severe storm development also cannot be ruled out this evening across central SD, in the vicinity of diffuse surface boundary. ...Northern MN... Strong storms have developed this evening across southeast MB, in the vicinity of a surface trough. Stronger large-scale ascent and greater storm coverage are expected to remain north of the international border, but development of an isolated strong storm or two cannot be ruled out through dusk across northwest MN, within a moderately buoyant environment. ...Eastern NE/SD into IA/northern MO/northeast KS late tonight... Elevated convection may develop late tonight from eastern NE/western IA into northeast KS/northwest MO, within a low-level warm advection regime. Moderate to strong elevated buoyancy, steep midlevel lapse rates, and modestly favorable effective shear could support at least transient storm organization. One or two southeastward-moving clusters may develop overnight within this regime, with a threat of isolated hail and strong to locally damaging gusts. ...Central/eastern MT into western ND late tonight... Elevated convection may increase overnight from central into northeast MT, in advance of a mid/upper-level shortwave trough moving across the interior Northwest. Moisture and elevated buoyancy will initially be modest, though small hail and gusty winds could accompany these storms overnight. There is some potential for this convection to intercept greater moisture/instability across northeast MT very late in the period, though at this time it appears that organized-severe potential may remain limited until near/after 12Z. ..Dean.. 08/07/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Wed Aug 06 2025 Valid 070100Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN/CENTRAL PLAINS AND MIDWEST...AND ALSO FOR NORTHWEST MN... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota, this evening into late tonight. ...Eastern WY/southeast MT into western/central SD/northwest NE... A favorable conditional environment remains in place this evening from eastern WY/far southeast MT into western SD/northwest NE, with moderate to strong buoyancy and effective shear of 40-50 kt. However, large-scale ascent is generally weak, and storms that developed across far eastern WY have been very isolated and relatively slow to intensify. A severe storm or two remains possible through the evening, with a threat of isolated hail and localized strong to severe gusts. Isolated strong to severe storm development also cannot be ruled out this evening across central SD, in the vicinity of diffuse surface boundary. ...Northern MN... Strong storms have developed this evening across southeast MB, in the vicinity of a surface trough. Stronger large-scale ascent and greater storm coverage are expected to remain north of the international border, but development of an isolated strong storm or two cannot be ruled out through dusk across northwest MN, within a moderately buoyant environment. ...Eastern NE/SD into IA/northern MO/northeast KS late tonight... Elevated convection may develop late tonight from eastern NE/western IA into northeast KS/northwest MO, within a low-level warm advection regime. Moderate to strong elevated buoyancy, steep midlevel lapse rates, and modestly favorable effective shear could support at least transient storm organization. One or two southeastward-moving clusters may develop overnight within this regime, with a threat of isolated hail and strong to locally damaging gusts. ...Central/eastern MT into western ND late tonight... Elevated convection may increase overnight from central into northeast MT, in advance of a mid/upper-level shortwave trough moving across the interior Northwest. Moisture and elevated buoyancy will initially be modest, though small hail and gusty winds could accompany these storms overnight. There is some potential for this convection to intercept greater moisture/instability across northeast MT very late in the period, though at this time it appears that organized-severe potential may remain limited until near/after 12Z. ..Dean.. 08/07/2025 Read more

No watches are valid as of Wed Aug 6 22:32:02 UTC 2025.

MD 1895 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WESTERN SD...NORTHEAST WY...AND FAR SOUTHEAST MT
Mesoscale Discussion 1895 NWS Storm Prediction Center Norman OK 0525 PM CDT Wed Aug 06 2025 Areas affected...Western SD...northeast WY...and far southeast MT Concerning...Severe potential...Watch unlikely Valid 062225Z - 070000Z Probability of Watch Issuance...5 percent SUMMARY...An isolated risk of large hail and locally severe gusts may persist for the next several hours. DISCUSSION...Isolated/cellular thunderstorms are evolving in the vicinity of the Black Hills, where an axis of middle/upper 50s dewpoints and diurnal heating have yielded weak surface-based buoyancy (per modified 18Z UNR and RAP soundings). While buoyancy is somewhat marginal, an elongated/straight hodograph (around 50 kt of effective shear) should promote transient convective organization/supercellular structure. Isolated large hail and locally severe gusts may accompany any longer-lived cells. However, minimal large-scale ascent (or even slight midlevel height rises) should keep the severe risk isolated/localized and brief. ..Weinman/Guyer.. 08/06/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...BYZ... LAT...LON 44640241 44240268 44030332 44140411 44370500 44480533 44700555 44990556 45370523 45570470 45590413 45440325 45220265 44970240 44640241 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

No Mesoscale Discussions are in effect as of Wed Aug 6 21:34:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0337 PM CDT Wed Aug 06 2025 Valid 081200Z - 141200Z A mid-level trough will gradually traverse the Interior West through the remainder of this week, ejecting into the Plains by this weekend. Thereafter, upper ridging will prevail west of the Rockies through most of next week. The passage of the mid-level trough on Day 3 (Friday) will encourage 20+ mph sustained southwesterly surface winds to overlap with 10-20 percent RH on a widespread basis across portions of the Great Basin into the Rockies. Given receptive fuels, up to 70 percent Critical probabilities have been introduced, particularly for areas expected to experience dry/windy conditions for several hours Friday afternoon. Across the Four Corners into the Southwest, enough mid-level moisture will linger each day through Sunday to support thunderstorm initiation given adequate mid-level buoyancy and orographic lift. These storms will develop atop a dry boundary layer, which should encourage at least a few dry strikes amid dry fuel beds, warranting 10 percent dry thunderstorm probabilities into the weekend. ..Squitieri.. 08/06/2025 ...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 0337 PM CDT Wed Aug 06 2025 Valid 081200Z - 141200Z A mid-level trough will gradually traverse the Interior West through the remainder of this week, ejecting into the Plains by this weekend. Thereafter, upper ridging will prevail west of the Rockies through most of next week. The passage of the mid-level trough on Day 3 (Friday) will encourage 20+ mph sustained southwesterly surface winds to overlap with 10-20 percent RH on a widespread basis across portions of the Great Basin into the Rockies. Given receptive fuels, up to 70 percent Critical probabilities have been introduced, particularly for areas expected to experience dry/windy conditions for several hours Friday afternoon. Across the Four Corners into the Southwest, enough mid-level moisture will linger each day through Sunday to support thunderstorm initiation given adequate mid-level buoyancy and orographic lift. These storms will develop atop a dry boundary layer, which should encourage at least a few dry strikes amid dry fuel beds, warranting 10 percent dry thunderstorm probabilities into the weekend. ..Squitieri.. 08/06/2025 ...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 0337 PM CDT Wed Aug 06 2025 Valid 081200Z - 141200Z A mid-level trough will gradually traverse the Interior West through the remainder of this week, ejecting into the Plains by this weekend. Thereafter, upper ridging will prevail west of the Rockies through most of next week. The passage of the mid-level trough on Day 3 (Friday) will encourage 20+ mph sustained southwesterly surface winds to overlap with 10-20 percent RH on a widespread basis across portions of the Great Basin into the Rockies. Given receptive fuels, up to 70 percent Critical probabilities have been introduced, particularly for areas expected to experience dry/windy conditions for several hours Friday afternoon. Across the Four Corners into the Southwest, enough mid-level moisture will linger each day through Sunday to support thunderstorm initiation given adequate mid-level buoyancy and orographic lift. These storms will develop atop a dry boundary layer, which should encourage at least a few dry strikes amid dry fuel beds, warranting 10 percent dry thunderstorm probabilities into the weekend. ..Squitieri.. 08/06/2025 ...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 0337 PM CDT Wed Aug 06 2025 Valid 081200Z - 141200Z A mid-level trough will gradually traverse the Interior West through the remainder of this week, ejecting into the Plains by this weekend. Thereafter, upper ridging will prevail west of the Rockies through most of next week. The passage of the mid-level trough on Day 3 (Friday) will encourage 20+ mph sustained southwesterly surface winds to overlap with 10-20 percent RH on a widespread basis across portions of the Great Basin into the Rockies. Given receptive fuels, up to 70 percent Critical probabilities have been introduced, particularly for areas expected to experience dry/windy conditions for several hours Friday afternoon. Across the Four Corners into the Southwest, enough mid-level moisture will linger each day through Sunday to support thunderstorm initiation given adequate mid-level buoyancy and orographic lift. These storms will develop atop a dry boundary layer, which should encourage at least a few dry strikes amid dry fuel beds, warranting 10 percent dry thunderstorm probabilities into the weekend. ..Squitieri.. 08/06/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more