SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

2 weeks 6 days ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Fri Aug 01 2025 Valid 011700Z - 021200Z Hot, very dry (minimum RH values less than 10%), and breezy (sustained surface winds of 15-20 mph) conditions are expected today across much of the central/southern Great Basin and neighboring portions of northwest Colorado and southwest Wyoming. As of 16Z, observations across this area suggest locally elevated conditions already ongoing with critical RH values present. Widespread elevated conditions are expected from midday through this evening as winds strengthen and RH values fall even further. The Elevated fire weather area was expanded across this region based on the latest high-resolution ensemble guidance. Elevated fire weather conditions are also likely across wind-prone portions of the Snake River Plain in Idaho, where several hours of sustained winds of 15-20 mph (with greater gusts) and minimum RH values near 15% are expected this afternoon/evening. Locally critical fire weather conditions are most likely across portions of southwest Utah, northwest Colorado into southwest Wyoming, and also the Snake River Plain. Though, coverage is forecast to be too spotty/brief to upgrade to Critical across these areas. The forecast for isolated dry thunderstorms over portions of the northern Great Basin/Intermountain West remains on-track. Gusty and erratic outflow winds will be possible nearby any thunderstorms. Please see the previous discussion for more information on today's fire weather forecast. ..Elliott.. 08/01/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Fri Aug 01 2025/ ...Synopsis... Between a large-scale ridge centered on the Southwest/northern Mexico and a broad/slow-moving midlevel trough crossing northern CA, enhanced west-southwesterly midlevel flow will overspread the southern Great Basin. Deep boundary-layer mixing into this enhanced flow aloft will yield hot, dry, and breezy conditions during the afternoon. Given receptive fuels, elevated fire-weather conditions are expected across southern NV into southern UT. Farther north, cool temperatures aloft/steep midlevel lapse rates accompanying the trough will promote another day of isolated to widely scattered high-based thunderstorms across the northern Great Basin/Intermountain West. Inverted-V profiles and 0.6-0.7 inch PW will favor mostly dry thunderstorms, with a risk of lightning-induced ignitions over receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more

SPC Aug 1, 2025 1630 UTC Day 1 Convective Outlook

2 weeks 6 days ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Fri Aug 01 2025 Valid 011630Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. ..Smith/Moore.. 08/01/2025 Read more