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SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Mon Nov 20 2023 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are currently not expected on Wednesday. ...Synopsis... Guidance varies with respect to upper-level pattern evolution on Wednesday, with recent GFS runs and the 20/00Z ECMWF depicting a relatively amplified shortwave trough moving eastward from the TN Valley toward the Carolinas, while other guidance depicts a broader positively tilted trough moving offshore earlier in the forecast period. Despite these differences, most guidance agrees that a cold front will be near or just offshore of coastal NC at the start of the period Wednesday morning, with the trailing portion of the front expected to move across the FL Peninsula through the day. ...Eastern NC and the Outer Banks... While some severe threat could evolve late in the D2/Tuesday period across eastern NC into the Outer Banks, most guidance suggests the effective warm sector will be very near the coast or offshore by the start of the D3/Wednesday period. As a result, severe probabilities were not included with this outlook. However, if the front is slower than currently anticipated, then some threat for isolated damaging wind and/or a brief tornado could briefly persist after 12Z Wednesday morning, within a weakly unstable but moist and strongly sheared environment. ..Dean.. 11/20/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0202 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern over the CONUS is forecast to continue amplifying as the upper low over the central US slides eastward. An attendant surface cyclone is projected to weaken as it moves northeastward across the TN Valley and into the eastern OH Valley by Tuesday evening. Widespread precipitation and cooler temperatures will overspread the eastern half of the US, limiting fire-weather concerns. To the west, eastern Pacific ridging will also intensify with strong high pressure developing within the Great Basin and the Intermountain West. Offshore flow will continue over parts of southern CA for the first half of the period, before weakening as the high pressure moves onto the Plains. Dry northerly winds are also expected over much of the central and southern High Plains. However, with limited fuels owing to cooler temperatures and recent precipitation, fire-weather concerns are expected to remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...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 0158 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...Synopsis... A deep mid-level trough over the central US will drive strong flow aloft southward over parts of southern CA and the lower CO River Valley while ridging develops over the eastern Pacific. High pressure over the northern Great Basin should support offshore flow over parts of southern CA through tonight and into early D2/Tuesday. ...Central Appalachians... Breezy easterly flow is expected over parts of western NC and eastern TN ahead of the surface low as it moves from OK into the mid MS Valley tonight. North of the stalled warm front, the low-level air mass remains relatively dry from the prior frontal passage. While RH values are not expected to reach critical levels, very strong low- and mid-level winds ahead of the surface low are expected to overspread areas of 90th percentile ERCs. Ongoing wildfire activity within the higher terrain could be impacted by strong east/southeast winds and mountain waves for several hours this afternoon into the evening. With this in mind, have opted to include a small elevated on the downwind side of the Smoky Mountains where strong winds could overlap with the driest fuels. Later tonight, widespread rain should develop and end the fire-weather threat. ...Southern High Plains... Very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the deep mid-level trough begins to move east. Aided by the low over OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns through the afternoon. ...Southern California... Strong flow aloft along the backside of the central US trough will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through tonight before winds begin to weaken into D2/Tuesday morning. However, marginally receptive fuels and the relatively brief period of offshore winds suggest any fire-weather concerns will remain localized. ..Lyons.. 11/20/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS A SMALL PART OF SOUTH AL AND THE FL PANHANDLE... ...SUMMARY... A couple tornadoes are possible across parts of south Alabama into the Florida Panhandle, mainly during the morning and early afternoon. Locally damaging winds and perhaps a couple brief tornadoes will also be possible from Georgia into the Carolinas Tuesday afternoon into Tuesday night. ...Synopsis... A vigorous mid/upper-level low is forecast to evolve into an open wave on Tuesday as it moves toward the lower Great Lakes and Northeast through the day. The related surface cyclone will take a similar track, with some weakening expected as it becomes increasingly displaced from the effective warm sector. A trailing cold front will continue to move through parts of the Southeast. One or more surface waves may develop along the effective warm front, with most guidance depicting consolidation of a surface cyclone near or off of the Mid Atlantic coast by Wednesday morning. Guidance continues to vary substantially with regard to large-scale trough evolution in the wake of the departing midlevel low, with the GFS (and now the 20/00Z ECMWF) continuing to amplify a shortwave near the Ozarks/lower MS Valley vicinity, while other guidance maintains a broad positively tilted trough that gradually moves eastward toward the Atlantic Coast. ...Parts of AL/GA and the FL Panhandle... While the primary surface cyclone will continue moving away from the region on Tuesday, convection will likely persist through the day within a confluent regime along/ahead of the front across parts of AL and FL Panhandle, and eventually move into parts of GA. Generally weak instability (with MLCAPE generally less than 500 J/kg away from the immediate coast) may tend to limit storm intensity, but favorable moisture and deep-layer shear will continue to support the potential for at least transient supercell structures. 0-1 km SRH generally in the 150-250 m2/s2 range will support some tornado threat where sufficient destabilization can occur. The threat may peak early in the day across south AL and the FL Panhandle, in association with any supercells that develop during the D1/Monday period and persist into Tuesday morning. A small Slight Risk has been included across this area, as a continuation of the threat from late on D1/Monday. Some threat for locally damaging gusts and/or a brief tornado may persist into the afternoon across parts of GA, in areas where modest diurnal heating can augment generally weak instability. ...Carolinas... A warm front is forecast to move northward across the Carolinas during the day, accompanied by low 60s F dewpoints. While wind profiles will become increasingly favorable for organized convection, instability is expected to remain very weak through the afternoon, due to weak lapse rates and rather widespread cloudiness and precipitation. There is some potential for an organized frontal band to develop and move eastward, which could pose a damaging-wind threat given the expected strength of low-level flow. A conditional Marginal Risk has been included for this threat, though the areal coverage of the convectively enhanced gust threat remains uncertain, due to diminishing instability with northward extent. Strong low-level shear could also support a brief tornado threat if pockets of somewhat greater instability can materialize. Somewhat richer moisture (with dewpoints in the mid 60s F) may advect northward into eastern NC Tuesday evening into the overnight, as low-level flow veers and strengthens some in response to the deepening cyclone near the Mid Atlantic coast. Some uptick in the tornado/wind threat is possible over eastern NC and the Outer Banks as this occurs, though uncertainty remains high regarding evolution of the upper trough (described above) and strength of large-scale ascent across the region during the overnight period. ..Dean.. 11/20/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CST Mon Nov 20 2023 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS A SMALL PART OF SOUTH AL AND THE FL PANHANDLE... ...SUMMARY... A couple tornadoes are possible across parts of south Alabama into the Florida Panhandle, mainly during the morning and early afternoon. Locally damaging winds and perhaps a couple brief tornadoes will also be possible from Georgia into the Carolinas Tuesday afternoon into Tuesday night. ...Synopsis... A vigorous mid/upper-level low is forecast to evolve into an open wave on Tuesday as it moves toward the lower Great Lakes and Northeast through the day. The related surface cyclone will take a similar track, with some weakening expected as it becomes increasingly displaced from the effective warm sector. A trailing cold front will continue to move through parts of the Southeast. One or more surface waves may develop along the effective warm front, with most guidance depicting consolidation of a surface cyclone near or off of the Mid Atlantic coast by Wednesday morning. Guidance continues to vary substantially with regard to large-scale trough evolution in the wake of the departing midlevel low, with the GFS (and now the 20/00Z ECMWF) continuing to amplify a shortwave near the Ozarks/lower MS Valley vicinity, while other guidance maintains a broad positively tilted trough that gradually moves eastward toward the Atlantic Coast. ...Parts of AL/GA and the FL Panhandle... While the primary surface cyclone will continue moving away from the region on Tuesday, convection will likely persist through the day within a confluent regime along/ahead of the front across parts of AL and FL Panhandle, and eventually move into parts of GA. Generally weak instability (with MLCAPE generally less than 500 J/kg away from the immediate coast) may tend to limit storm intensity, but favorable moisture and deep-layer shear will continue to support the potential for at least transient supercell structures. 0-1 km SRH generally in the 150-250 m2/s2 range will support some tornado threat where sufficient destabilization can occur. The threat may peak early in the day across south AL and the FL Panhandle, in association with any supercells that develop during the D1/Monday period and persist into Tuesday morning. A small Slight Risk has been included across this area, as a continuation of the threat from late on D1/Monday. Some threat for locally damaging gusts and/or a brief tornado may persist into the afternoon across parts of GA, in areas where modest diurnal heating can augment generally weak instability. ...Carolinas... A warm front is forecast to move northward across the Carolinas during the day, accompanied by low 60s F dewpoints. While wind profiles will become increasingly favorable for organized convection, instability is expected to remain very weak through the afternoon, due to weak lapse rates and rather widespread cloudiness and precipitation. There is some potential for an organized frontal band to develop and move eastward, which could pose a damaging-wind threat given the expected strength of low-level flow. A conditional Marginal Risk has been included for this threat, though the areal coverage of the convectively enhanced gust threat remains uncertain, due to diminishing instability with northward extent. Strong low-level shear could also support a brief tornado threat if pockets of somewhat greater instability can materialize. Somewhat richer moisture (with dewpoints in the mid 60s F) may advect northward into eastern NC Tuesday evening into the overnight, as low-level flow veers and strengthens some in response to the deepening cyclone near the Mid Atlantic coast. Some uptick in the tornado/wind threat is possible over eastern NC and the Outer Banks as this occurs, though uncertainty remains high regarding evolution of the upper trough (described above) and strength of large-scale ascent across the region during the overnight period. ..Dean.. 11/20/2023 Read more