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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0648 AM CST Wed Nov 06 2024 Valid 061300Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE LOWER FLORIDA KEYS... ...SUMMARY... A couple of brief tornadoes will be possible within outermost fringes of the circulation of Hurricane Rafael, from late morning into the evening, across the Keys and the far southwestern Florida Peninsula. ...Synopsis... In mid/upper levels, mean troughing will remain over the Rocky Mountain States as a strong subsynoptic trough -- now evident in moisture-channel imagery over the Four Corners region -- strengthens to a closed cyclone. The associate 500-mb low is expected to become better-developed throughout the period as it closes off and retrogrades south-southwestward across AZ. In response to these developments, height rises are forecast across the southern Plains and Gulf Coast region, while ridging also builds westward from the Bermuda high. In turn, this should shift Hurricane Rafael westward toward the central Gulf, following today's crossing of western Cuba, per NHC forecast. At the surface, 11Z analysis showed a frontal-wave low over ON north of Lake Huron, with cold front across Lower MI, IN, western parts of KY/TN/MS, central LA, and the shelf waters off the TX Gulf Coast. Under height rises and weakening/largely parallel flow aloft, the frontal segment south of about I-40 should become quasistationary through the remainder of the period. Given those factors, weak midlevel lapse rates, and negligible mid/upper support, associated thunderstorms should have an unconditional severe potential below 5% for gusts and less than 2% for tornado, with no large-hail threat. ...FL Keys and vicinity... Although Rafael will be pivoting more westward away from the region than previous forecast cycles suggested, and is a relatively small hurricane, the influence of ambient shear imparts a northeastward tilt to the overall convective pattern. This will lead to the passage of peripheral cells and perhaps (over the Lower Keys) banding features. The track forecast also should result in the largest low-level shear remaining west and south of EYW, but still-favorable hodographs passing across the outlook area from this afternoon into tonight. As such, the outlook lines are shifted slightly westward, in keeping with NHC track-forecast trends, but still kept at 5% "slight" levels over the Lower Keys for this cycle. See latest NHC advisories for forecast track/intensity of Rafael, and tropical-related watches/warnings. ..Edwards/Mosier.. 11/06/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Wed Nov 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Modest severe potential remains apparent during parts of the extended period. A mid/upper low over the central High Plains at 12Z Saturday should pivot northeastward towards the Upper Midwest as it becomes an open wave. A belt of strong mid-level southwesterlies should overlap with the northwestern periphery of a modified low-level moisture plume emanating north from the western Gulf. This plume is expected to be narrower to the north-northwest of the Ark-La-Tex. Combined with probable ongoing convection in the warm conveyor ahead of the weak surface front, the overall severe threat on D4 should be confined/low-end. While outlier guidance indicates the possibility of TC Rafael approaching the coastal LA vicinity this weekend, ensemble trends and latest NHC forecast suggest it will probably remain over the western Gulf. Guidance consensus still indicates an amplified upper trough should progress into the West early next week, with this feature reaching the central states mid-week. This may eventually overlap a broadening warm/moist sector emanating north from the western Gulf across the south-central states. But poor run-to-run continuity and large ensemble spread persist with the evolution of this trough. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Wed Nov 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TO NORTH TX... ...SUMMARY... Isolated severe thunderstorms are possible through early evening Friday across parts of south-central to north Texas. ...TX... A mid/upper low should deepen as it moves from the central NM vicinity to the central High Plains. A belt of fast mid-level flow will largely remain within the southeast arc of this cyclone. At the surface, a minor low over west TX should similarly advance north towards western KS. A cold front will arc to its south in mainly a north-south orientation through central portions of TX. Linear clusters of convection will likely be ongoing at 12Z Friday across parts of west TX near the surface cyclone. This activity will probably persist through the day, especially with northern extent where activity should largely remain elevated. This will limit surface-based destabilization north, with more prominent surface heating probable from central TX southward. Guidance differs on just how far north instability will develop. This yields uncertainty on the demarcation of the low-probability severe area where low-level to deep-layer shear will be strong. Given the north-northeast track of the upper low and associated weak surface cyclone, forcing for ascent should wane towards late day along the south-central TX portion of the front. Progressively weaker low-level shear indicates more of a hail/wind threat from central TX south. Overall setup suggests severe coverage should remain isolated into the afternoon and likely diminish after sunset. ..Grams.. 11/06/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Wed Nov 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...Synopsis... On the backside of a deep/closed midlevel low over the Southwest, strong deep-layer northerly flow will persist across southern CA -- downstream of an amplified large-scale ridge over the West Coast. This upper-level pattern will maintain an expansive surface anticyclone over the Intermountain West, with a related tight offshore pressure gradient and Santa Ana winds across southern CA. ...Southern California... While the offshore pressure gradient will be gradually weakening across southern CA (compared to Day 1/Wednesday), LAX-DAG should still be around -5 mb from Thursday morning through Thursday afternoon -- a strong indicator of continued critical fire-weather conditions. High-resolution guidance is in good agreement, depicting a continuation of 20+ mph sustained northeasterly surface winds (with gusts upwards of 50 mph) and lower teens to single-digit RH. The best overlap and longest duration of these conditions is once again expected across the wind-prone corridor of northern Los Angeles and southern Ventura Counties, where Critical highlights are in place. ..Weinman.. 11/06/2024 ...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 0200 AM CST Wed Nov 06 2024 Valid 061200Z - 071200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR NORTHERN LOS ANGELES AND SOUTHERN VENTURA COUNTIES... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN CALIFORNIA... ...Synopsis... Between a highly amplified large-scale ridge over the West Coast, and a deep midlevel trough extending from the northern Plains into the Four Corners, a belt of strong deep-layer northerly flow will overspread the Great Basin into southern CA. In response, an expansive surface anticyclone will be reinforced over the Intermountain West. These factors will yield a strong offshore pressure gradient and ample upper-level support across southern CA, leading to a strong Santa Ana wind event. ...Southern California... From Wednesday morning into Wednesday night, the tightening offshore pressure gradient (LAX-DAG peaking around -7 to -8 mb), coupled with the strong deep-layer north-northeasterly flow directed toward the coast, will favor sustained northeasterly surface winds of 30+ mph and gusts upwards of 60 mph across much of southern CA. Higher gusts (70+ mph) are expected over the wind-prone mountains and slopes. These strong/gusty winds will combine with lower teens/single-digit RH, leading to dangerous fire-weather conditions. The most volatile and long-duration combination of strong winds and low RH over receptive fuels is expected over the wind-prone Santa Ana corridor of southern Ventura and northern Los Angeles Counties -- where Extremely Critical fire-weather conditions are expected. ...Northern/Central California... The tight pressure gradient peripheral to the strong surface anticyclone and enhanced deep-layer northerly flow will also favor strong northerly surface winds amid low RH over the western Sacramento Valley to the coast. Given modestly receptive fuels across this region, elevated to locally critical fire-weather conditions are expected from Wednesday morning into Wednesday night. ..Weinman.. 11/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more