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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

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

MD 2255 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF EASTERN LOUISIANA INTO SOUTHERN MISSISSIPPI AND SOUTHWEST ALABAMA
Mesoscale Discussion 2255 NWS Storm Prediction Center Norman OK 0534 AM CST Tue Dec 10 2024 Areas affected...parts of eastern Louisiana into southern Mississippi and southwest Alabama Concerning...Severe potential...Watch unlikely Valid 101134Z - 101400Z Probability of Watch Issuance...20 percent SUMMARY...A brief/weak tornado or locally damaging gust may occur during the next several hours. Coverage of severe is not expected to warrant a watch. DISCUSSION...A slow-moving cold front currently extends from southwest LA into central and northeast MS, with generally weak surface winds. However, storms have increased in coverage near and just ahead of the boundary within the moistening air mass. Surface analysis shows dewpoints in the upper 60s F to near 70 F, along with 1-1.5 mb 2-hr pressure falls into southwest MS. Winds around 850 mb are around 30 kt out of the southwest, with 0-1 km SRH across the warm sector generally from 100 to 150 m2/s2. MUCAPE per objective analysis is generally in the 500-1000 J/kg range. In aggregate, the marginal instability, shear, and ascent may remain sufficient for a low risk of a brief tornado or locally damaging gusts over the next few hours as storms develop east/northeast across MS and into western AL. Instability may not be strong enough to support very long-lived supercells, but a QLCS-type tornado may occur in association with the stronger outflows. ..Jewell.. 12/10/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BMX...MOB...JAN...LIX... LAT...LON 30309133 31769032 32218966 32708834 32628768 32248746 31898755 31128830 30319065 30239105 30309133 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 AM CST Tue Dec 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL GULF COAST REGION INTO CENTRAL/SOUTHERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... A few strong to severe thunderstorms are possible across portions of the central Gulf Coast region into central/southern Georgia and the Florida Panhandle through tonight. ...Synopsis... In mid/upper levels, mean troughing over the central CONUS will evolve from positively to near neutrally tilted through the period, in conjunction with two predominant subsynoptic-scale processes: 1. South-southeastward digging of a cyclone now over extreme northern MB, reaching the MB/ON border east of Lake Winnipeg by 12Z tomorrow; 2. Eastward shift of a strong, basal shortwave trough -- now evident in moisture-channel imagery over northern NM into south-central AZ -- absorbing a weaker/trailing perturbation and reaching from middle TN to central LA by the end of the period. As this occurs, a surface cold front -- analyzed at 11Z from a low near BNA southwestward across northwestern MS, central LA, middle TX Coast, and deep south TX -- should extend from western PA across the southern Appalachians and southwestern AL, to southeastern LA, by 00Z. A low-level, prefrontal confluence/convergence zone may intensify this evening and tonight over portions of the FL Panhandle, southeastern AL and southwestern GA. The cold front should approach and perhaps overtake the confluence zone by 12Z, as it reaches a position from central PA across the western Carolinas, to near a MCN-AAF line, then over the northeastern/central Gulf. ...Southeast... Widely scattered, ongoing thunderstorms clusters are apparent across portions of southern MS into southeastern LA, with a marginal potential for a brief tornado or strong-severe gust. See SPC mesoscale discussion 2255 for near-term coverage of this scenario. Similarly sporadic, isolated and marginal tornado and severe-gust potential will exist throughout today and tonight with convection along and just ahead of the cold front, as well as slowly increasing convective coverage from late afternoon through overnight in the prefrontal convergence zone. The warm-sector environment will remain characterized by a nearly saturated boundary layer with surface dewpoints commonly in the upper 60s to near 70 F along the coast, to mid 60s well inland, amidst nearly moist-adiabatic low-level lapse rates. Somewhat greater boundary-layer instability is possible this afternoon in the inflow to the near-frontal convection, as modest heating occurs through cloud breaks. That my offset weak midlevel lapse rates enough to support peak MLCAPE around 1000 J/kg from southeastern LA to south-central AL, decreasing northeastward as well as eastward. An axis of lesser buoyancy -- with MLCAPE remaining in the 500-800 J/kg range, should shift eastward tonight near the confluence line, in support of convection there. Deep shear should increase from late this afternoon through tonight with the more neutral tilt of the larger-scale trough aloft, and related tightening of the mid/upper height gradient over the warm sector. While strongest flow aloft will remain behind the front, effective-shear magnitudes of 45-55 kt and elongated low-level hodographs are forecast from the northeastern Gulf Coast to the Carolinas. As the basal shortwave trough approaches (but remains behind the cold front), the LLJ should strengthen to 45-55 kt tonight over southern GA, reaching 55-65 kt over eastern NC, with lengthening but only somewhat curved low-level hodographs. The northeastward extent of the conditional severe potential may extend into near-coastal SC/NC; however, poor low- and middle-level lapse rates (with stable layers apparent in forecast soundings) are precluding any expansion of unconditional probabilities northeastward for this outlook cycle. The main (yet marginal) severe threat for the Carolinas still appears to hold off until early day 2. ..Edwards/Jewell.. 12/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 AM CST Tue Dec 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL GULF COAST REGION INTO CENTRAL/SOUTHERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... A few strong to severe thunderstorms are possible across portions of the central Gulf Coast region into central/southern Georgia and the Florida Panhandle through tonight. ...Synopsis... In mid/upper levels, mean troughing over the central CONUS will evolve from positively to near neutrally tilted through the period, in conjunction with two predominant subsynoptic-scale processes: 1. South-southeastward digging of a cyclone now over extreme northern MB, reaching the MB/ON border east of Lake Winnipeg by 12Z tomorrow; 2. Eastward shift of a strong, basal shortwave trough -- now evident in moisture-channel imagery over northern NM into south-central AZ -- absorbing a weaker/trailing perturbation and reaching from middle TN to central LA by the end of the period. As this occurs, a surface cold front -- analyzed at 11Z from a low near BNA southwestward across northwestern MS, central LA, middle TX Coast, and deep south TX -- should extend from western PA across the southern Appalachians and southwestern AL, to southeastern LA, by 00Z. A low-level, prefrontal confluence/convergence zone may intensify this evening and tonight over portions of the FL Panhandle, southeastern AL and southwestern GA. The cold front should approach and perhaps overtake the confluence zone by 12Z, as it reaches a position from central PA across the western Carolinas, to near a MCN-AAF line, then over the northeastern/central Gulf. ...Southeast... Widely scattered, ongoing thunderstorms clusters are apparent across portions of southern MS into southeastern LA, with a marginal potential for a brief tornado or strong-severe gust. See SPC mesoscale discussion 2255 for near-term coverage of this scenario. Similarly sporadic, isolated and marginal tornado and severe-gust potential will exist throughout today and tonight with convection along and just ahead of the cold front, as well as slowly increasing convective coverage from late afternoon through overnight in the prefrontal convergence zone. The warm-sector environment will remain characterized by a nearly saturated boundary layer with surface dewpoints commonly in the upper 60s to near 70 F along the coast, to mid 60s well inland, amidst nearly moist-adiabatic low-level lapse rates. Somewhat greater boundary-layer instability is possible this afternoon in the inflow to the near-frontal convection, as modest heating occurs through cloud breaks. That my offset weak midlevel lapse rates enough to support peak MLCAPE around 1000 J/kg from southeastern LA to south-central AL, decreasing northeastward as well as eastward. An axis of lesser buoyancy -- with MLCAPE remaining in the 500-800 J/kg range, should shift eastward tonight near the confluence line, in support of convection there. Deep shear should increase from late this afternoon through tonight with the more neutral tilt of the larger-scale trough aloft, and related tightening of the mid/upper height gradient over the warm sector. While strongest flow aloft will remain behind the front, effective-shear magnitudes of 45-55 kt and elongated low-level hodographs are forecast from the northeastern Gulf Coast to the Carolinas. As the basal shortwave trough approaches (but remains behind the cold front), the LLJ should strengthen to 45-55 kt tonight over southern GA, reaching 55-65 kt over eastern NC, with lengthening but only somewhat curved low-level hodographs. The northeastward extent of the conditional severe potential may extend into near-coastal SC/NC; however, poor low- and middle-level lapse rates (with stable layers apparent in forecast soundings) are precluding any expansion of unconditional probabilities northeastward for this outlook cycle. The main (yet marginal) severe threat for the Carolinas still appears to hold off until early day 2. ..Edwards/Jewell.. 12/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 AM CST Tue Dec 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL GULF COAST REGION INTO CENTRAL/SOUTHERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... A few strong to severe thunderstorms are possible across portions of the central Gulf Coast region into central/southern Georgia and the Florida Panhandle through tonight. ...Synopsis... In mid/upper levels, mean troughing over the central CONUS will evolve from positively to near neutrally tilted through the period, in conjunction with two predominant subsynoptic-scale processes: 1. South-southeastward digging of a cyclone now over extreme northern MB, reaching the MB/ON border east of Lake Winnipeg by 12Z tomorrow; 2. Eastward shift of a strong, basal shortwave trough -- now evident in moisture-channel imagery over northern NM into south-central AZ -- absorbing a weaker/trailing perturbation and reaching from middle TN to central LA by the end of the period. As this occurs, a surface cold front -- analyzed at 11Z from a low near BNA southwestward across northwestern MS, central LA, middle TX Coast, and deep south TX -- should extend from western PA across the southern Appalachians and southwestern AL, to southeastern LA, by 00Z. A low-level, prefrontal confluence/convergence zone may intensify this evening and tonight over portions of the FL Panhandle, southeastern AL and southwestern GA. The cold front should approach and perhaps overtake the confluence zone by 12Z, as it reaches a position from central PA across the western Carolinas, to near a MCN-AAF line, then over the northeastern/central Gulf. ...Southeast... Widely scattered, ongoing thunderstorms clusters are apparent across portions of southern MS into southeastern LA, with a marginal potential for a brief tornado or strong-severe gust. See SPC mesoscale discussion 2255 for near-term coverage of this scenario. Similarly sporadic, isolated and marginal tornado and severe-gust potential will exist throughout today and tonight with convection along and just ahead of the cold front, as well as slowly increasing convective coverage from late afternoon through overnight in the prefrontal convergence zone. The warm-sector environment will remain characterized by a nearly saturated boundary layer with surface dewpoints commonly in the upper 60s to near 70 F along the coast, to mid 60s well inland, amidst nearly moist-adiabatic low-level lapse rates. Somewhat greater boundary-layer instability is possible this afternoon in the inflow to the near-frontal convection, as modest heating occurs through cloud breaks. That my offset weak midlevel lapse rates enough to support peak MLCAPE around 1000 J/kg from southeastern LA to south-central AL, decreasing northeastward as well as eastward. An axis of lesser buoyancy -- with MLCAPE remaining in the 500-800 J/kg range, should shift eastward tonight near the confluence line, in support of convection there. Deep shear should increase from late this afternoon through tonight with the more neutral tilt of the larger-scale trough aloft, and related tightening of the mid/upper height gradient over the warm sector. While strongest flow aloft will remain behind the front, effective-shear magnitudes of 45-55 kt and elongated low-level hodographs are forecast from the northeastern Gulf Coast to the Carolinas. As the basal shortwave trough approaches (but remains behind the cold front), the LLJ should strengthen to 45-55 kt tonight over southern GA, reaching 55-65 kt over eastern NC, with lengthening but only somewhat curved low-level hodographs. The northeastward extent of the conditional severe potential may extend into near-coastal SC/NC; however, poor low- and middle-level lapse rates (with stable layers apparent in forecast soundings) are precluding any expansion of unconditional probabilities northeastward for this outlook cycle. The main (yet marginal) severe threat for the Carolinas still appears to hold off until early day 2. ..Edwards/Jewell.. 12/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 AM CST Tue Dec 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL GULF COAST REGION INTO CENTRAL/SOUTHERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... A few strong to severe thunderstorms are possible across portions of the central Gulf Coast region into central/southern Georgia and the Florida Panhandle through tonight. ...Synopsis... In mid/upper levels, mean troughing over the central CONUS will evolve from positively to near neutrally tilted through the period, in conjunction with two predominant subsynoptic-scale processes: 1. South-southeastward digging of a cyclone now over extreme northern MB, reaching the MB/ON border east of Lake Winnipeg by 12Z tomorrow; 2. Eastward shift of a strong, basal shortwave trough -- now evident in moisture-channel imagery over northern NM into south-central AZ -- absorbing a weaker/trailing perturbation and reaching from middle TN to central LA by the end of the period. As this occurs, a surface cold front -- analyzed at 11Z from a low near BNA southwestward across northwestern MS, central LA, middle TX Coast, and deep south TX -- should extend from western PA across the southern Appalachians and southwestern AL, to southeastern LA, by 00Z. A low-level, prefrontal confluence/convergence zone may intensify this evening and tonight over portions of the FL Panhandle, southeastern AL and southwestern GA. The cold front should approach and perhaps overtake the confluence zone by 12Z, as it reaches a position from central PA across the western Carolinas, to near a MCN-AAF line, then over the northeastern/central Gulf. ...Southeast... Widely scattered, ongoing thunderstorms clusters are apparent across portions of southern MS into southeastern LA, with a marginal potential for a brief tornado or strong-severe gust. See SPC mesoscale discussion 2255 for near-term coverage of this scenario. Similarly sporadic, isolated and marginal tornado and severe-gust potential will exist throughout today and tonight with convection along and just ahead of the cold front, as well as slowly increasing convective coverage from late afternoon through overnight in the prefrontal convergence zone. The warm-sector environment will remain characterized by a nearly saturated boundary layer with surface dewpoints commonly in the upper 60s to near 70 F along the coast, to mid 60s well inland, amidst nearly moist-adiabatic low-level lapse rates. Somewhat greater boundary-layer instability is possible this afternoon in the inflow to the near-frontal convection, as modest heating occurs through cloud breaks. That my offset weak midlevel lapse rates enough to support peak MLCAPE around 1000 J/kg from southeastern LA to south-central AL, decreasing northeastward as well as eastward. An axis of lesser buoyancy -- with MLCAPE remaining in the 500-800 J/kg range, should shift eastward tonight near the confluence line, in support of convection there. Deep shear should increase from late this afternoon through tonight with the more neutral tilt of the larger-scale trough aloft, and related tightening of the mid/upper height gradient over the warm sector. While strongest flow aloft will remain behind the front, effective-shear magnitudes of 45-55 kt and elongated low-level hodographs are forecast from the northeastern Gulf Coast to the Carolinas. As the basal shortwave trough approaches (but remains behind the cold front), the LLJ should strengthen to 45-55 kt tonight over southern GA, reaching 55-65 kt over eastern NC, with lengthening but only somewhat curved low-level hodographs. The northeastward extent of the conditional severe potential may extend into near-coastal SC/NC; however, poor low- and middle-level lapse rates (with stable layers apparent in forecast soundings) are precluding any expansion of unconditional probabilities northeastward for this outlook cycle. The main (yet marginal) severe threat for the Carolinas still appears to hold off until early day 2. ..Edwards/Jewell.. 12/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 AM CST Tue Dec 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL GULF COAST REGION INTO CENTRAL/SOUTHERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... A few strong to severe thunderstorms are possible across portions of the central Gulf Coast region into central/southern Georgia and the Florida Panhandle through tonight. ...Synopsis... In mid/upper levels, mean troughing over the central CONUS will evolve from positively to near neutrally tilted through the period, in conjunction with two predominant subsynoptic-scale processes: 1. South-southeastward digging of a cyclone now over extreme northern MB, reaching the MB/ON border east of Lake Winnipeg by 12Z tomorrow; 2. Eastward shift of a strong, basal shortwave trough -- now evident in moisture-channel imagery over northern NM into south-central AZ -- absorbing a weaker/trailing perturbation and reaching from middle TN to central LA by the end of the period. As this occurs, a surface cold front -- analyzed at 11Z from a low near BNA southwestward across northwestern MS, central LA, middle TX Coast, and deep south TX -- should extend from western PA across the southern Appalachians and southwestern AL, to southeastern LA, by 00Z. A low-level, prefrontal confluence/convergence zone may intensify this evening and tonight over portions of the FL Panhandle, southeastern AL and southwestern GA. The cold front should approach and perhaps overtake the confluence zone by 12Z, as it reaches a position from central PA across the western Carolinas, to near a MCN-AAF line, then over the northeastern/central Gulf. ...Southeast... Widely scattered, ongoing thunderstorms clusters are apparent across portions of southern MS into southeastern LA, with a marginal potential for a brief tornado or strong-severe gust. See SPC mesoscale discussion 2255 for near-term coverage of this scenario. Similarly sporadic, isolated and marginal tornado and severe-gust potential will exist throughout today and tonight with convection along and just ahead of the cold front, as well as slowly increasing convective coverage from late afternoon through overnight in the prefrontal convergence zone. The warm-sector environment will remain characterized by a nearly saturated boundary layer with surface dewpoints commonly in the upper 60s to near 70 F along the coast, to mid 60s well inland, amidst nearly moist-adiabatic low-level lapse rates. Somewhat greater boundary-layer instability is possible this afternoon in the inflow to the near-frontal convection, as modest heating occurs through cloud breaks. That my offset weak midlevel lapse rates enough to support peak MLCAPE around 1000 J/kg from southeastern LA to south-central AL, decreasing northeastward as well as eastward. An axis of lesser buoyancy -- with MLCAPE remaining in the 500-800 J/kg range, should shift eastward tonight near the confluence line, in support of convection there. Deep shear should increase from late this afternoon through tonight with the more neutral tilt of the larger-scale trough aloft, and related tightening of the mid/upper height gradient over the warm sector. While strongest flow aloft will remain behind the front, effective-shear magnitudes of 45-55 kt and elongated low-level hodographs are forecast from the northeastern Gulf Coast to the Carolinas. As the basal shortwave trough approaches (but remains behind the cold front), the LLJ should strengthen to 45-55 kt tonight over southern GA, reaching 55-65 kt over eastern NC, with lengthening but only somewhat curved low-level hodographs. The northeastward extent of the conditional severe potential may extend into near-coastal SC/NC; however, poor low- and middle-level lapse rates (with stable layers apparent in forecast soundings) are precluding any expansion of unconditional probabilities northeastward for this outlook cycle. The main (yet marginal) severe threat for the Carolinas still appears to hold off until early day 2. ..Edwards/Jewell.. 12/10/2024 Read more