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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Thu Aug 07 2025 Valid 091200Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Isolated to scattered severe storms will be possible on Saturday from the southern Plains to the Great Lakes, with the greatest threat concentrated from northeastern Iowa into central and northeastern Wisconsin. ...Upper Midwest/Great Lakes... A mid-level trough will move eastward across the northern Plains on Saturday, as cyclonically curved southwesterly flow remains over the Upper Midwest. At the surface, a cold front will advance southeastward into Iowa, Wisconsin and the western Great Lakes. As surface temperatures warm during the day, moderate and potentially strong instability is forecast ahead of the front. Increasing low-level convergence ahead of the front should result in scattered thunderstorms by afternoon. A more persistent convective complex could persist from late afternoon into the evening, with this cluster projected to move east-southeastward across southern Wisconsin and northeastern Iowa during the early evening. Along this track, MLCAPE is forecast to be in the 3000 to 5000 J/kg range. In addition, low-level lapse rates are forecast to be steep, and moderate deep-layer shear should be in place. This should be enough for severe storm development. Damaging wind gusts will be possible with the more intense line segments. Hail could also occur. ...Southern and Central Plains/Mid Missouri Valley... West-southwesterly mid-level flow will be in place across much of the southern and central Plains on Saturday. At the surface, a cold front is forecast to move southward through the central Plains. Near the front, surface dewpoints in the 60s and lower 70s F will contribute to moderate instability by afternoon. Within this airmass, large-scale ascent is forecast to remain weak. However, isolated convective initiation will be possible along parts of the front as low-level convergence becomes maximized. Due to steep low to mid-level lapse rates and sufficient deep-layer shear, an isolated severe threat could develop. A few severe gusts and hail will be the primary threats. ..Broyles.. 08/07/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Moderate-strong midlevel westerly flow will be in place across the Great Basin into the central Rockies -- between a robust midlevel trough over the northern Rockies/High Plains and midlevel anticyclone over the southern Rockies/High Plains. ...Great Basin into the Central Rockies... Similar to Day 1/Thursday, a diurnally deepening boundary layer will extend well into the moderate-strong westerly flow aloft. This will promote an expansive overlap of single-digit to lower teens RH and 20-25 mph sustained westerly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another day of critical fire-weather conditions. ...Dry Thunderstorms - Southwest into the central Rockies... Diurnal heating/mixing beneath an established midlevel moisture plume from the Southwest into the central Rockies will favor another day of isolated to widely scattered high-based thunderstorms during the afternoon. Associated inverted-V soundings and 0.50 to 0.75 inch PW will support mostly dry storms, capable of producing lightning-induced ignitions over dry fuels and gusty/erratic outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Moderate-strong midlevel westerly flow will be in place across the Great Basin into the central Rockies -- between a robust midlevel trough over the northern Rockies/High Plains and midlevel anticyclone over the southern Rockies/High Plains. ...Great Basin into the Central Rockies... Similar to Day 1/Thursday, a diurnally deepening boundary layer will extend well into the moderate-strong westerly flow aloft. This will promote an expansive overlap of single-digit to lower teens RH and 20-25 mph sustained westerly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another day of critical fire-weather conditions. ...Dry Thunderstorms - Southwest into the central Rockies... Diurnal heating/mixing beneath an established midlevel moisture plume from the Southwest into the central Rockies will favor another day of isolated to widely scattered high-based thunderstorms during the afternoon. Associated inverted-V soundings and 0.50 to 0.75 inch PW will support mostly dry storms, capable of producing lightning-induced ignitions over dry fuels and gusty/erratic outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Moderate-strong midlevel westerly flow will be in place across the Great Basin into the central Rockies -- between a robust midlevel trough over the northern Rockies/High Plains and midlevel anticyclone over the southern Rockies/High Plains. ...Great Basin into the Central Rockies... Similar to Day 1/Thursday, a diurnally deepening boundary layer will extend well into the moderate-strong westerly flow aloft. This will promote an expansive overlap of single-digit to lower teens RH and 20-25 mph sustained westerly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another day of critical fire-weather conditions. ...Dry Thunderstorms - Southwest into the central Rockies... Diurnal heating/mixing beneath an established midlevel moisture plume from the Southwest into the central Rockies will favor another day of isolated to widely scattered high-based thunderstorms during the afternoon. Associated inverted-V soundings and 0.50 to 0.75 inch PW will support mostly dry storms, capable of producing lightning-induced ignitions over dry fuels and gusty/erratic outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Moderate-strong midlevel westerly flow will be in place across the Great Basin into the central Rockies -- between a robust midlevel trough over the northern Rockies/High Plains and midlevel anticyclone over the southern Rockies/High Plains. ...Great Basin into the Central Rockies... Similar to Day 1/Thursday, a diurnally deepening boundary layer will extend well into the moderate-strong westerly flow aloft. This will promote an expansive overlap of single-digit to lower teens RH and 20-25 mph sustained westerly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another day of critical fire-weather conditions. ...Dry Thunderstorms - Southwest into the central Rockies... Diurnal heating/mixing beneath an established midlevel moisture plume from the Southwest into the central Rockies will favor another day of isolated to widely scattered high-based thunderstorms during the afternoon. Associated inverted-V soundings and 0.50 to 0.75 inch PW will support mostly dry storms, capable of producing lightning-induced ignitions over dry fuels and gusty/erratic outflow winds. ..Weinman.. 08/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Thu Aug 07 2025 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... ...Synopsis... Moderate-strong midlevel westerly flow will be in place across the Great Basin into the central Rockies -- between a robust midlevel trough over the northern Rockies/High Plains and midlevel anticyclone over the southern Rockies/High Plains. ...Great Basin into the Central Rockies... Similar to Day 1/Thursday, a diurnally deepening boundary layer will extend well into the moderate-strong westerly flow aloft. This will promote an expansive overlap of single-digit to lower teens RH and 20-25 mph sustained westerly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another day of critical fire-weather conditions. ...Dry Thunderstorms - Southwest into the central Rockies... Diurnal heating/mixing beneath an established midlevel moisture plume from the Southwest into the central Rockies will favor another day of isolated to widely scattered high-based thunderstorms during the afternoon. Associated inverted-V soundings and 0.50 to 0.75 inch PW will support mostly dry storms, capable of producing lightning-induced ignitions over dry fuels and gusty/erratic 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 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 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