Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Sat Aug 23 2025 Valid 231300Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE FRONT RANGE/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe storms are possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...Front Range/Central High Plains... Multiple subtle upper ridge-peripheral impulses and a belt of moderately strong northwesterly winds aloft will influence the region as low-level upslope flow increases late today within the post-frontal environment. At least widely scattered thunderstorm development is expected initially over the mountains, with subsequent intensification as storms develop east-southeastward into a moderately unstable air mass, with buoyancy maximized near/immediately east of the urban corridor/I-25. Steep mid-level lapse rates and 40+ kt effective shear will support the possibility of isolated supercells capable of large hail and some locally stronger wind gusts through early evening. ...Midwest/Great Lakes... A few showers and thunderstorms will likely develop along a cold front as it moves across the Great Lakes/Midwest this afternoon. Warm 700mb temperatures in the presence of only low 60s dewpoints will limit overall buoyancy and updraft strength, likely keeping severe-storm potential minimal. ..Guyer/Kerr.. 08/23/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Sat Aug 23 2025 Valid 231300Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE FRONT RANGE/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe storms are possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...Front Range/Central High Plains... Multiple subtle upper ridge-peripheral impulses and a belt of moderately strong northwesterly winds aloft will influence the region as low-level upslope flow increases late today within the post-frontal environment. At least widely scattered thunderstorm development is expected initially over the mountains, with subsequent intensification as storms develop east-southeastward into a moderately unstable air mass, with buoyancy maximized near/immediately east of the urban corridor/I-25. Steep mid-level lapse rates and 40+ kt effective shear will support the possibility of isolated supercells capable of large hail and some locally stronger wind gusts through early evening. ...Midwest/Great Lakes... A few showers and thunderstorms will likely develop along a cold front as it moves across the Great Lakes/Midwest this afternoon. Warm 700mb temperatures in the presence of only low 60s dewpoints will limit overall buoyancy and updraft strength, likely keeping severe-storm potential minimal. ..Guyer/Kerr.. 08/23/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Sat Aug 23 2025 Valid 231300Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE FRONT RANGE/CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe storms are possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...Front Range/Central High Plains... Multiple subtle upper ridge-peripheral impulses and a belt of moderately strong northwesterly winds aloft will influence the region as low-level upslope flow increases late today within the post-frontal environment. At least widely scattered thunderstorm development is expected initially over the mountains, with subsequent intensification as storms develop east-southeastward into a moderately unstable air mass, with buoyancy maximized near/immediately east of the urban corridor/I-25. Steep mid-level lapse rates and 40+ kt effective shear will support the possibility of isolated supercells capable of large hail and some locally stronger wind gusts through early evening. ...Midwest/Great Lakes... A few showers and thunderstorms will likely develop along a cold front as it moves across the Great Lakes/Midwest this afternoon. Warm 700mb temperatures in the presence of only low 60s dewpoints will limit overall buoyancy and updraft strength, likely keeping severe-storm potential minimal. ..Guyer/Kerr.. 08/23/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CDT Sat Aug 23 2025 Valid 261200Z - 311200Z ...DISCUSSION... ...Tuesday/Day 4 to Thursday/Day 6... A large-scale trough will remain in place across the eastern U.S. on Tuesday, as an area of surface high pressure remains dominant across much of the eastern half of the nation. Non-severe thunderstorms may develop on the western periphery of post-frontal airmass, over parts of the southern and central High Plains on Tuesday and Wednesday. On Thursday, low-level moisture return is forecast to take place across the southern and central Plains. A pocket of moderate instability will be possible across parts of Oklahoma, where scattered thunderstorms may develop during the afternoon. In spite of this, deep-layer shear is forecast to remain relatively weak, suggesting any severe threat will be marginal. ...Friday/Day 7 and Saturday/Day 8... From Friday into Saturday, northwesterly mid-level flow will remain in place over parts of much of the central and eastern part of the nation. At the surface, a moist airmass will likely be located over parts of the Gulf Coast states, where scattered thunderstorms will be possible each day. Deep-layer shear is forecast be relatively weak across most of the region from Friday into Saturday, suggesting that any severe threat will remain localized. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CDT Sat Aug 23 2025 Valid 261200Z - 311200Z ...DISCUSSION... ...Tuesday/Day 4 to Thursday/Day 6... A large-scale trough will remain in place across the eastern U.S. on Tuesday, as an area of surface high pressure remains dominant across much of the eastern half of the nation. Non-severe thunderstorms may develop on the western periphery of post-frontal airmass, over parts of the southern and central High Plains on Tuesday and Wednesday. On Thursday, low-level moisture return is forecast to take place across the southern and central Plains. A pocket of moderate instability will be possible across parts of Oklahoma, where scattered thunderstorms may develop during the afternoon. In spite of this, deep-layer shear is forecast to remain relatively weak, suggesting any severe threat will be marginal. ...Friday/Day 7 and Saturday/Day 8... From Friday into Saturday, northwesterly mid-level flow will remain in place over parts of much of the central and eastern part of the nation. At the surface, a moist airmass will likely be located over parts of the Gulf Coast states, where scattered thunderstorms will be possible each day. Deep-layer shear is forecast be relatively weak across most of the region from Friday into Saturday, suggesting that any severe threat will remain localized. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CDT Sat Aug 23 2025 Valid 261200Z - 311200Z ...DISCUSSION... ...Tuesday/Day 4 to Thursday/Day 6... A large-scale trough will remain in place across the eastern U.S. on Tuesday, as an area of surface high pressure remains dominant across much of the eastern half of the nation. Non-severe thunderstorms may develop on the western periphery of post-frontal airmass, over parts of the southern and central High Plains on Tuesday and Wednesday. On Thursday, low-level moisture return is forecast to take place across the southern and central Plains. A pocket of moderate instability will be possible across parts of Oklahoma, where scattered thunderstorms may develop during the afternoon. In spite of this, deep-layer shear is forecast to remain relatively weak, suggesting any severe threat will be marginal. ...Friday/Day 7 and Saturday/Day 8... From Friday into Saturday, northwesterly mid-level flow will remain in place over parts of much of the central and eastern part of the nation. At the surface, a moist airmass will likely be located over parts of the Gulf Coast states, where scattered thunderstorms will be possible each day. Deep-layer shear is forecast be relatively weak across most of the region from Friday into Saturday, suggesting that any severe threat will remain localized. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CDT Sat Aug 23 2025 Valid 261200Z - 311200Z ...DISCUSSION... ...Tuesday/Day 4 to Thursday/Day 6... A large-scale trough will remain in place across the eastern U.S. on Tuesday, as an area of surface high pressure remains dominant across much of the eastern half of the nation. Non-severe thunderstorms may develop on the western periphery of post-frontal airmass, over parts of the southern and central High Plains on Tuesday and Wednesday. On Thursday, low-level moisture return is forecast to take place across the southern and central Plains. A pocket of moderate instability will be possible across parts of Oklahoma, where scattered thunderstorms may develop during the afternoon. In spite of this, deep-layer shear is forecast to remain relatively weak, suggesting any severe threat will be marginal. ...Friday/Day 7 and Saturday/Day 8... From Friday into Saturday, northwesterly mid-level flow will remain in place over parts of much of the central and eastern part of the nation. At the surface, a moist airmass will likely be located over parts of the Gulf Coast states, where scattered thunderstorms will be possible each day. Deep-layer shear is forecast be relatively weak across most of the region from Friday into Saturday, suggesting that any severe threat will remain localized. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CDT Sat Aug 23 2025 Valid 261200Z - 311200Z ...DISCUSSION... ...Tuesday/Day 4 to Thursday/Day 6... A large-scale trough will remain in place across the eastern U.S. on Tuesday, as an area of surface high pressure remains dominant across much of the eastern half of the nation. Non-severe thunderstorms may develop on the western periphery of post-frontal airmass, over parts of the southern and central High Plains on Tuesday and Wednesday. On Thursday, low-level moisture return is forecast to take place across the southern and central Plains. A pocket of moderate instability will be possible across parts of Oklahoma, where scattered thunderstorms may develop during the afternoon. In spite of this, deep-layer shear is forecast to remain relatively weak, suggesting any severe threat will be marginal. ...Friday/Day 7 and Saturday/Day 8... From Friday into Saturday, northwesterly mid-level flow will remain in place over parts of much of the central and eastern part of the nation. At the surface, a moist airmass will likely be located over parts of the Gulf Coast states, where scattered thunderstorms will be possible each day. Deep-layer shear is forecast be relatively weak across most of the region from Friday into Saturday, suggesting that any severe threat will remain localized. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms across the continental U.S. on Monday and Monday night appears to be low. ...DISCUSSION... A large-scale cyclonic flow pattern will remain over much of the eastern half of the U.S. on Monday. At the surface, a large area of high pressure will settle in across the north-central U.S., as a relative cool and dry airmass remains in place from the eastern Gulf Coast states northward into the Great Lakes. A front is forecast to move through New England, along which isolated thunderstorm development is expected during the day. Instability near the front should remain weak, and the potential for severe storms appears low. In the central U.S., northwesterly mid-level flow will be in place on Monday. A slow-moving front is forecast over the southern High Plains. Scattered thunderstorms will be possible in the afternoon near the front from south-central Colorado into the northern Texas Panhandle. Along and near the front, instability is expected to remain weak, suggesting the severe potential should remain low. Elsewhere across the continental U.S., a severe threat is not expected Monday or Monday night. ..Broyles.. 08/23/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms across the continental U.S. on Monday and Monday night appears to be low. ...DISCUSSION... A large-scale cyclonic flow pattern will remain over much of the eastern half of the U.S. on Monday. At the surface, a large area of high pressure will settle in across the north-central U.S., as a relative cool and dry airmass remains in place from the eastern Gulf Coast states northward into the Great Lakes. A front is forecast to move through New England, along which isolated thunderstorm development is expected during the day. Instability near the front should remain weak, and the potential for severe storms appears low. In the central U.S., northwesterly mid-level flow will be in place on Monday. A slow-moving front is forecast over the southern High Plains. Scattered thunderstorms will be possible in the afternoon near the front from south-central Colorado into the northern Texas Panhandle. Along and near the front, instability is expected to remain weak, suggesting the severe potential should remain low. Elsewhere across the continental U.S., a severe threat is not expected Monday or Monday night. ..Broyles.. 08/23/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms across the continental U.S. on Monday and Monday night appears to be low. ...DISCUSSION... A large-scale cyclonic flow pattern will remain over much of the eastern half of the U.S. on Monday. At the surface, a large area of high pressure will settle in across the north-central U.S., as a relative cool and dry airmass remains in place from the eastern Gulf Coast states northward into the Great Lakes. A front is forecast to move through New England, along which isolated thunderstorm development is expected during the day. Instability near the front should remain weak, and the potential for severe storms appears low. In the central U.S., northwesterly mid-level flow will be in place on Monday. A slow-moving front is forecast over the southern High Plains. Scattered thunderstorms will be possible in the afternoon near the front from south-central Colorado into the northern Texas Panhandle. Along and near the front, instability is expected to remain weak, suggesting the severe potential should remain low. Elsewhere across the continental U.S., a severe threat is not expected Monday or Monday night. ..Broyles.. 08/23/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0157 AM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ..Weinman.. 08/23/2025 ...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 0157 AM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ..Weinman.. 08/23/2025 ...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 0157 AM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ..Weinman.. 08/23/2025 ...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 0157 AM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ..Weinman.. 08/23/2025 ...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 Sat Aug 23 2025 Valid 231200Z - 241200Z ...Synopsis... An expansive midlevel high will remain in place over the Four Corners vicinity, while deepening monsoonal moisture continues spreading northward across the Great Basin into the Northwest. Along the western periphery of the midlevel high, an unseasonably hot/unstable air mass will persist across much of CA into the Great Basin, where another day of diurnally driven showers and thunderstorms are expected. While the gradually deepening monsoonal moisture will favor a mix of wet/dry thunderstorms, a dry/deeply mixed sub-cloud layer will tend to limit precipitation accumulations over many areas. As a result, isolated lightning-induced ignitions will be possible over dry fuels, along with gusty/erratic outflow winds. ..Weinman.. 08/23/2025 ...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 Sat Aug 23 2025 Valid 231200Z - 241200Z ...Synopsis... An expansive midlevel high will remain in place over the Four Corners vicinity, while deepening monsoonal moisture continues spreading northward across the Great Basin into the Northwest. Along the western periphery of the midlevel high, an unseasonably hot/unstable air mass will persist across much of CA into the Great Basin, where another day of diurnally driven showers and thunderstorms are expected. While the gradually deepening monsoonal moisture will favor a mix of wet/dry thunderstorms, a dry/deeply mixed sub-cloud layer will tend to limit precipitation accumulations over many areas. As a result, isolated lightning-induced ignitions will be possible over dry fuels, along with gusty/erratic outflow winds. ..Weinman.. 08/23/2025 ...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 Sat Aug 23 2025 Valid 231200Z - 241200Z ...Synopsis... An expansive midlevel high will remain in place over the Four Corners vicinity, while deepening monsoonal moisture continues spreading northward across the Great Basin into the Northwest. Along the western periphery of the midlevel high, an unseasonably hot/unstable air mass will persist across much of CA into the Great Basin, where another day of diurnally driven showers and thunderstorms are expected. While the gradually deepening monsoonal moisture will favor a mix of wet/dry thunderstorms, a dry/deeply mixed sub-cloud layer will tend to limit precipitation accumulations over many areas. As a result, isolated lightning-induced ignitions will be possible over dry fuels, along with gusty/erratic outflow winds. ..Weinman.. 08/23/2025 ...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 Sat Aug 23 2025 Valid 231200Z - 241200Z ...Synopsis... An expansive midlevel high will remain in place over the Four Corners vicinity, while deepening monsoonal moisture continues spreading northward across the Great Basin into the Northwest. Along the western periphery of the midlevel high, an unseasonably hot/unstable air mass will persist across much of CA into the Great Basin, where another day of diurnally driven showers and thunderstorms are expected. While the gradually deepening monsoonal moisture will favor a mix of wet/dry thunderstorms, a dry/deeply mixed sub-cloud layer will tend to limit precipitation accumulations over many areas. As a result, isolated lightning-induced ignitions will be possible over dry fuels, along with gusty/erratic outflow winds. ..Weinman.. 08/23/2025 ...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 0115 AM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Isolated strong to severe thunderstorms are possible across eastern Colorado into western Kansas Sunday afternoon and evening. ...Eastern Colorado/Western Kansas... A mid-level large-scale trough will dig southeastward into the eastern U.S. on Sunday, as northwesterly flow remains over much of the central and northern U.S. At the surface, an area of high pressure will move southward across the Great Plains. A slow-moving front will remain in place in eastern Colorado along the western periphery of the surface high. Elevated thunderstorms are expected to develop well to the east of the boundary across parts of western Kansas Sunday morning. Closer to the boundary itself, moderate instability is forecast to develop during the day across the eastern third of Colorado. As surface heating takes place and as low-level convergence increases near the boundary, scattered surface-based convection initiation is expected during the afternoon. This convection is forecast to increase in coverage during the late afternoon, being supported by large-scale ascent associated with a subtle shortwave trough moving through the central Plains. The storms are expected to move southeastward across eastern Colorado into southwest Kansas, with a few storms continuing into the early to mid evening. NAM forecast soundings in the vicinity of the instability axis around 21Z have MLCAPE near 2500 J/kg, with 0-6 km shear around 40 knots. This combined with 700-500 mb lapse rates of 7 to 7.5 C/km may be enough for isolated severe storms. A potential will exist for a supercell or two. Hail and marginally severe wind gusts will be the primary threats. ..Broyles.. 08/23/2025 Read more