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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE EASTERN NC VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across many of the East Coast States. The most probable area for a few tornadoes and damaging winds is centered on eastern North Carolina during Wednesday afternoon. ...Synopsis... A longwave trough will extend from south-central Canada to the northern Gulf Coast on Wednesday morning. A vigorous shortwave impulse embedded within the basal portion of the trough will rapidly advance into the Mid-Atlantic States by early evening and pivot north to the St. Lawrence Valley Wednesday night. This will yield an increasingly negative tilt to the broad trough, with associated intensification of deep-layer flow fields and surface cyclogenesis. ...Eastern NC vicinity... A plume of mid 60s surface dew points are expected to advect north across parts of the eastern Carolinas into southeast VA by Wednesday afternoon. Boundary-layer destabilization should be tempered by preceding weak convection within the warm conveyor and pervasive cloudiness limiting insolation. Still, consensus of guidance suggests the relatively warmest surface temperatures should occur across eastern NC. Amid weak lapse rates, buoyancy should remain meager to around 500 J/kg along the coast. Even so, favorable timing of the synoptic evolution with respect to the diurnal heating cycle should yield a strongly forced convective line along the progressive cold front. Some guidance suggests a pre-frontal band of surface-based storms might separately develop in low-level confluence over coastal NC and the Outer Banks. At least a few embedded supercells are plausible, yielding a tornado and wind threat. The progressive nature of the front suggests the tornado threat may be more sporadic with shorter-lived circulations embedded in the line until it shifts offshore. ...Eastern Gulf/South Atlantic Coasts... Deep convection should be ongoing across parts of the FL Panhandle into south GA at 12Z Wednesday. Despite the time of day, the northern periphery of rich eastern Gulf moisture in conjunction with enhanced low-level hodograph curvature will support a localized tornado/wind threat through midday. Some potential may persist into the afternoon over parts of the north/central FL Peninsula but low-level winds will become more veered with time as the shortwave trough rapidly advances away from this region. The northern extent of the threat into GA/SC will be predicated on the degree of surface-based destabilization, which appears to be a relative min in the Southeast. ...Northeast... Primary thunderstorm activity should be in the form of sporadic lightning flashes amid scant elevated buoyancy within the low-level warm conveyor. Some CAM guidance does suggest a low-topped convective line may develop along the eastward-surging cold front during the afternoon/evening. Surface-based instability may remain negligible and lightning production appears unlikely. But with intensifying wind fields, potential remains for strong surface gusts capable of tree damage. ..Grams.. 12/10/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...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 1044 AM CST Tue Dec 10 2024 Valid 101700Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... Critical to Extremely Critical fire weather conditions continue across southern California this morning. Peak wind gusts of 50-70 mph (localized 80-90 mph) with a fire ongoing in Malibu. Guidance suggests that the peak winds have occurred this morning, with gradual weakening through the afternoon. However, Critical to locally Extremely Critical conditions will continue across the mountains and foothills through the rest of the afternoon and into the evening. Some lingering Elevated to Critical conditions will continue into Wednesday morning. Minor changes were made to bring the Critical to the coast in Ventura and Los Angeles county in alignment with ongoing surface observations. ..Thornton.. 12/10/2024 .PREV DISCUSSION... /ISSUED 0102 AM CST Tue Dec 10 2024/ ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2256 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF CENTRAL ALABAMA INTO FAR WESTERN GEORGIA
Mesoscale Discussion 2256 NWS Storm Prediction Center Norman OK 0954 AM CST Tue Dec 10 2024 Areas affected...portions of central Alabama into far western Georgia Concerning...Severe potential...Watch possible Valid 101554Z - 101730Z Probability of Watch Issuance...40 percent SUMMARY...The severe threat should continue to gradually increase through the morning, into the afternoon hours. A few tornadoes and/or severe gusts are the main threats. Convective trends are being monitored for the need of a Tornado Watch. An upgrade to a Slight Risk is also expected for portions of the region. DISCUSSION...Thunderstorms have gradually been increasing in coverage and intensity across central AL within a low-level moisture axis. Recently, a supercell structure has developed and may have produced a tornado in western AL. Immediately preceding these storms is a 30+ kt southwesterly LLJ that is expected to intensify into the late morning/early afternoon hours. At the same time, surface heating may boost MLCAPE over 500 J/kg amid upper 60s F surface dewpoints and modest tropospheric lapse rates. Latest observations show a diffuse baroclinic zone across central AL into far western GA. Here, hodographs will be most enlarged amid a potentially strengthening LLJ and aforementioned adequate buoyancy. Additional supercell structures are possible this afternoon, with a few tornadoes and severe gusts the main threats. Questions remain regarding when an uptick in severe may be realized (i.e. late morning vs. early afternoon), so it is unclear when a Tornado Watch may need to be issued. Convective trends will continue to be monitored for the need of a Tornado Watch at some point today. Furthermore, given the anticipated uptick in severe, a Slight Risk will be issued for the upcoming 1630Z Day 1 Convective Outlook. ..Squitieri/Hart.. 12/10/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FFC...BMX... LAT...LON 32948400 32578424 32388529 32268635 32348705 32478757 32678789 33218741 33578665 33638560 33458447 33298423 32948400 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Tue Dec 10 2024 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FROM CENTRAL ALABAMA INTO WEST-CENTRAL GEORGIA... ...SUMMARY... A few strong to severe thunderstorms may affect portions of central Alabama into west-central Georgia through this evening. ...AL/GA... The subtropical jet extends across the Gulf Coast region today, with several subtle shortwave troughs suggested in water vapor imagery that will affect parts of FL/AL/GA. Ample low-level moisture is present across central/southern AL/GA with dewpoints in the mid-upper 60s - yielding MUCAPE around 500 J/kg. Several 12z CAM solutions indicate a mesoscale low-level jet max that will intensify ahead of the cluster of showers/thunderstorms over west-central AL. This will lead to enhanced low-level vertical shear and forcing, providing support for a few supercell/bowing storm structures and the risk of a tornado or two and damaging wind gusts. Given these trends, have opted to upgrade this corridor to SLGT. Refer to MCD #2256 for further short-term details. ...Carolinas... Late tonight, the rapidly amplifying upper jet over the TN valley will lead to an organizing band of showers and low-topped thunderstorms along the cold front over SC/NC. It still looks like the main intensification of this line will occur after 12z, so will not expand the MRGL risk farther east. However, this area will continue to be re-evaluated in later outlooks. ..Hart/Squitieri.. 12/10/2024 Read more