Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Mon Aug 18 2025 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN WI AND NORTHERN IL...AND ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...Mid MS Valley... Extensive outflow from last night's MCS currently extends from extreme southwest WI southwestward through eastern IA and north-central MO into eastern KS. This outflow has been moving quickly eastward/southeastward this morning, and this trend is expected to continue, although some slowing of its progression speed is possible over time. The downstream airmass across from southern WI and IL is characterized by dewpoints in the low to mid 70s. Mid-level lapse rates are generally poor across the region, but heating of this very moist airmass will still result in strong to very strong buoyancy (i.e. MLCAPE around 3000 J/kg) by late afternoon. Strong to severe storms are possible along this outflow as it impinges on this moist and buoyant airmass. Current trends suggest the greatest severe potential will exist this afternoon across southern WI and northern IL, where slightly stronger mid-level flow, backed surface winds, and an east-west baroclinic zone exists. Recently issued MCD 1983 addresses the short-term severe potential for this area. ...Central High Plains into the northern/central Plains... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Additional isolated storms are possible farther north across western NE into the Black Hills region. Much of this area is within a corridor of modest mid-level flow on the northern periphery of the upper ridging covering the southern CONUS. Resulting modest shear may be enough for hail production with the initial development before these high-based storms trend towards outflow-dominant structures with time. These storms may persist into the evening, with an attendant threat for strong to severe gusts progressing into central NE before weakening. ...MO/AR... Clear skies and strong diurnal heating are expected across central/southern MO and much of AR. Temperatures in the upper 90s are expected, with dewpoints remaining in the mid 60s despite strong mixing. These hot and humid conditions will result in strong buoyancy this afternoon, with most guidance suggesting MLCAPE around 2000 J/kg. Shear will be weak, yielding mostly disorganized multicells, but the strongest storms will be capable of locally damaging wind gusts. ..Mosier/Wendt.. 08/18/2025 Read more

No watches are valid as of Mon Aug 18 16:34:02 UTC 2025.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...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 1011 AM CDT Mon Aug 18 2025 Valid 181700Z - 191200Z ...NO CRITICAL AREAS... Minimum RH near and below 10% with very poor RH recovery overnight is expected from central Nevada through the West Slope and into northwest Arizona and southeast California resulting in long burning periods. The forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 08/18/2025 .PREV DISCUSSION... /ISSUED 0201 AM CDT Mon Aug 18 2025/ ...Synopsis... As upper-level ridging builds rapidly over the West, modest south-southwest deep layer flow and efficient daytime mixing of a deep/dry boundary layer will support sustained south-southwest winds of 10-12 mph across southern/northern NV this afternoon. Winds combined with relative humidity nearing 10 percent will support short duration and localized elevated fire weather conditions across southern, central and northeastern NV where very dry fuels exist. ...Northern Rockies/Central Idaho Mountains... A mid-level trough will persist over the Northwest on the periphery of the building upper ridge. Residual Pacific/monsoon moisture and daytime heating will result in isolated showers and thunderstorms across northern ID and higher terrain of western MT. Although northeast thunderstorm motions of 25-30 knots will limit rainfall, fuels remain mostly non-receptive to new lightning ignitions across the Northern Rockies, precluding introduction of dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 AM CDT Mon Aug 18 2025 Valid 181300Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE CENTRAL/NORTHERN PLAINS...AND OVER PARTS OF THE MIDWEST.... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...IA/WI/IL... A long-lived MCS continues to track eastward across central IA this morning. Visible satellite imagery shows the potential for considerable daytime heating ahead of this activity across parts of eastern IA/southern WI/northern IL, where temperatures will warm into the 90s. Ample low-level moisture will yield afternoon MLCAPE values around 3000 J/kg, along with sufficient westerly flow aloft for some convective organization. It is unclear whether current activity will intensify, or new storms will form later today. Regardless, this region will see the potential for strong/severe storms capable of damaging wind gusts. A tornado or two is also possible, given the backed low-level winds and east-west baroclinic zone along the WI/IL border. Have added a SLGT risk for this scenario. ...Northeast CO into SD/NE/KS... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Other more isolated storms are expected farther north across western NE into the Black Hills region. All of these storms will be relatively high-based, posing a risk of damaging wind gusts. Sufficient westerly flow will also aid in a few transient supercells capable of large hail. These storms may persist into the evening, tracking into central NE before weakening. ...MO/AR... Clear skies are evident this morning across central/southern MO and much of AR. Hot and humid conditions will ensue with temperatures reaching the upper 90s. Most CAM solutions suggest widely scattered afternoon thunderstorm development in this environment of steep low-level lapse rates and 1500-2000 J/kg of MLCAPE. The strongest storms will be capable of locally damaging wind gusts. ..Hart/Dean.. 08/18/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 AM CDT Mon Aug 18 2025 Valid 181300Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE CENTRAL/NORTHERN PLAINS...AND OVER PARTS OF THE MIDWEST.... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...IA/WI/IL... A long-lived MCS continues to track eastward across central IA this morning. Visible satellite imagery shows the potential for considerable daytime heating ahead of this activity across parts of eastern IA/southern WI/northern IL, where temperatures will warm into the 90s. Ample low-level moisture will yield afternoon MLCAPE values around 3000 J/kg, along with sufficient westerly flow aloft for some convective organization. It is unclear whether current activity will intensify, or new storms will form later today. Regardless, this region will see the potential for strong/severe storms capable of damaging wind gusts. A tornado or two is also possible, given the backed low-level winds and east-west baroclinic zone along the WI/IL border. Have added a SLGT risk for this scenario. ...Northeast CO into SD/NE/KS... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Other more isolated storms are expected farther north across western NE into the Black Hills region. All of these storms will be relatively high-based, posing a risk of damaging wind gusts. Sufficient westerly flow will also aid in a few transient supercells capable of large hail. These storms may persist into the evening, tracking into central NE before weakening. ...MO/AR... Clear skies are evident this morning across central/southern MO and much of AR. Hot and humid conditions will ensue with temperatures reaching the upper 90s. Most CAM solutions suggest widely scattered afternoon thunderstorm development in this environment of steep low-level lapse rates and 1500-2000 J/kg of MLCAPE. The strongest storms will be capable of locally damaging wind gusts. ..Hart/Dean.. 08/18/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 AM CDT Mon Aug 18 2025 Valid 181300Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE CENTRAL/NORTHERN PLAINS...AND OVER PARTS OF THE MIDWEST.... ...SUMMARY... Strong to severe storms capable of damaging winds are possible in parts of the Midwest today. Widely scattered storms with large hail and severe winds are possible in parts of the central/northern Plains through tonight. ...IA/WI/IL... A long-lived MCS continues to track eastward across central IA this morning. Visible satellite imagery shows the potential for considerable daytime heating ahead of this activity across parts of eastern IA/southern WI/northern IL, where temperatures will warm into the 90s. Ample low-level moisture will yield afternoon MLCAPE values around 3000 J/kg, along with sufficient westerly flow aloft for some convective organization. It is unclear whether current activity will intensify, or new storms will form later today. Regardless, this region will see the potential for strong/severe storms capable of damaging wind gusts. A tornado or two is also possible, given the backed low-level winds and east-west baroclinic zone along the WI/IL border. Have added a SLGT risk for this scenario. ...Northeast CO into SD/NE/KS... Strong heating and ample low/mid level moisture will promote the development of scattered thunderstorms by mid-afternoon over the foothills and plains of central/eastern CO. Other more isolated storms are expected farther north across western NE into the Black Hills region. All of these storms will be relatively high-based, posing a risk of damaging wind gusts. Sufficient westerly flow will also aid in a few transient supercells capable of large hail. These storms may persist into the evening, tracking into central NE before weakening. ...MO/AR... Clear skies are evident this morning across central/southern MO and much of AR. Hot and humid conditions will ensue with temperatures reaching the upper 90s. Most CAM solutions suggest widely scattered afternoon thunderstorm development in this environment of steep low-level lapse rates and 1500-2000 J/kg of MLCAPE. The strongest storms will be capable of locally damaging wind gusts. ..Hart/Dean.. 08/18/2025 Read more