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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...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 1259 PM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/21/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Nov 21 2023/ ...Synopsis... Shortwave ridging across the central CONUS will persist into D2/Wednesday as the eastern trough weakens and moves offshore. Stronger westerly flow aloft north of the western ridge will support weak lee cyclogenesis over the central High Plains. Otherwise, broad high pressure is expected over much of the US and surface winds should remain light, with the exception of some stronger offshore gusts over southern CA early in the day. Cooler temperatures, weak winds, moderate RH, and widespread recent rainfall will limit overall fire-weather concerns throughout much of the country. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Tue Nov 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN NC... ...SUMMARY... A brief tornado and a localized severe gust are possible on Wednesday morning across eastern North Carolina and the Outer Banks. ...Eastern NC... A mid-level vorticity max on the backside of a broad trough over the central states will dig southeast from the Lower MO Valley to the Deep South by Wednesday morning and then eject eastward and move off the Carolina coast by evening. The surface cold front will be displaced well east of this feature, likely in vicinity of the NC coastal plain at 12Z. In the warm conveyor ahead of the front, a broad swath of lower-topped convection and deeper convective elements will be ongoing from the GA to southeast VA coast. The prefrontal environment across eastern NC will be characterized by rich low-level moisture and strong low-level to deep-layer shear, but poor lapse rates and widespread precipitation will limit destabilization prior to frontal passage. The potential for organized storm structures within this environment remains uncertain due to the meager instability. But a transient supercell or stronger line segment remains possible, with an attendant threat of a brief tornado and locally damaging wind prior to midday. ..Grams.. 11/21/2023 Read more

MD 2281 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE FLORIDA PANHANDLE
Mesoscale Discussion 2281 NWS Storm Prediction Center Norman OK 1036 AM CST Tue Nov 21 2023 Areas affected...portions of the Florida Panhandle Concerning...Severe potential...Watch unlikely Valid 211636Z - 211730Z Probability of Watch Issuance...20 percent SUMMARY...A brief tornado or two may accompany low-topped supercells as they approach the FL Panhandle shoreline. The severe threat should stay isolated over the next couple of hours, so a WW issuance is not expected in the near-term. DISCUSSION...Low-topped supercells have developed within the low-level warm-air-advection axis and are approaching the western FL Panhandle. Along the coast, strong veering and strengthening of the low-level wind profile supports enlarged hodographs. While dewpoints are reaching 70 F along the coast, weak diurnal heating beneath poor tropospheric lapse rates are resulting in thin CAPE profiles (with SBCAPE struggling to exceed 500 J/kg). As such, the strong low-level shear may support a brief tornado across the western FL Panhandle, but the severe threat should remain sparse at best over the next couple of hours, and a WW issuance not anticipated. Should more appreciable surface heating occur through the afternoon ahead of an approaching cold front, a relatively more robust severe threat could materialize. The region will be monitored more carefully for such a scenario and the need for a WW issuance later today. ..Squitieri/Gleason.. 11/21/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TAE...MOB... LAT...LON 30188678 30668638 30938595 30888533 30428470 29988485 29848538 29908620 30188678 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Tue Nov 21 2023 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ALABAMA...THE FLORIDA PANHANDLE...AND SOUTHWESTERN GEORGIA... ...SUMMARY... A few tornadoes and isolated damaging gusts still appear possible today across parts of southern Alabama, southwestern Georgia, and the Florida Panhandle. Isolated damaging gusts and perhaps a tornado also remain possible this afternoon through tonight from central/northern Georgia into the Carolinas and southeastern Virginia. ...Synopsis... A large mid/upper-level cyclone over the Great Lakes this morning will continue to move eastward today. A trailing, positively tilted upper trough extends across the Midwest into the mid/lower MS Valley and southern Plains. The primary surface low over the Midwest is also forecast to develop slowly east-northeastward toward the Lower Great Lakes through tonight. A trailing cold front will progress eastward today and tonight across the Southeast and Mid-Atlantic states as a secondary surface low eventually forms over VA/MD and develops quickly northeastward across the coastal Mid-Atlantic. ...Central to Northeast Gulf Coast States... Swaths of warm-advection-related precipitation and widespread cloud cover have hindered daytime heating so far this morning across southern AL, the FL Panhandle, and GA. Still, some clearing has recently been noted between the cold front ongoing precipitation. Most guidance suggests that surface temperatures reaching into the low 70s will be needed for sufficient boundary-layer destabilization to support surface-based thunderstorms. Even with this modest heating, poor lapse rates aloft will likely hinder the degree of MLCAPE across the warm sector this afternoon. This should temper updraft intensities to some extent. But, latest VWPs from area radars show rather strong low-level and deep-layer shear are still present across this region. Any robust convection that can develop along/near the cold front this afternoon could become supercellular, with an associated threat for a few tornadoes and isolated damaging winds. But, confidence remains low that enough instability will develop to support intense thunderstorms. Have therefore maintained the low-confidence Slight Risk across this region with minimal changes. ...Georgia into the Carolinas and Southeastern Virginia... Widespread cloud cover and areas of precipitation remain prevalent from GA into the NC/SC and VA, with a warm front/retreating wedge front delineating the northern extent of low-level moisture return. Instability should remain fairly weak through the period with northeastward extent from central/northern GA into the Carolinas. This limits confidence in thunderstorm intensities this afternoon. Still, a conditional threat for damaging wind gusts and perhaps a tornado or two exists with mainly linear convection that can develop/strengthen along the eastward-moving cold front this afternoon and evening. Late tonight, a low-topped line of convection may develop along the front from NC into southeastern VA and vicinity. While instability is forecast to remain minimal, strong flow at low/mid levels may still reach the surface through convective downdrafts. Have expanded the Marginal Risk for isolated damaging winds northward a bit based on this potential. Confidence in supercells developing across coastal/eastern NC in the last few hours of the period remains low. ..Gleason/Moore.. 11/21/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Tue Nov 21 2023 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ALABAMA...THE FLORIDA PANHANDLE...AND SOUTHWESTERN GEORGIA... ...SUMMARY... A few tornadoes and isolated damaging gusts still appear possible today across parts of southern Alabama, southwestern Georgia, and the Florida Panhandle. Isolated damaging gusts and perhaps a tornado also remain possible this afternoon through tonight from central/northern Georgia into the Carolinas and southeastern Virginia. ...Synopsis... A large mid/upper-level cyclone over the Great Lakes this morning will continue to move eastward today. A trailing, positively tilted upper trough extends across the Midwest into the mid/lower MS Valley and southern Plains. The primary surface low over the Midwest is also forecast to develop slowly east-northeastward toward the Lower Great Lakes through tonight. A trailing cold front will progress eastward today and tonight across the Southeast and Mid-Atlantic states as a secondary surface low eventually forms over VA/MD and develops quickly northeastward across the coastal Mid-Atlantic. ...Central to Northeast Gulf Coast States... Swaths of warm-advection-related precipitation and widespread cloud cover have hindered daytime heating so far this morning across southern AL, the FL Panhandle, and GA. Still, some clearing has recently been noted between the cold front ongoing precipitation. Most guidance suggests that surface temperatures reaching into the low 70s will be needed for sufficient boundary-layer destabilization to support surface-based thunderstorms. Even with this modest heating, poor lapse rates aloft will likely hinder the degree of MLCAPE across the warm sector this afternoon. This should temper updraft intensities to some extent. But, latest VWPs from area radars show rather strong low-level and deep-layer shear are still present across this region. Any robust convection that can develop along/near the cold front this afternoon could become supercellular, with an associated threat for a few tornadoes and isolated damaging winds. But, confidence remains low that enough instability will develop to support intense thunderstorms. Have therefore maintained the low-confidence Slight Risk across this region with minimal changes. ...Georgia into the Carolinas and Southeastern Virginia... Widespread cloud cover and areas of precipitation remain prevalent from GA into the NC/SC and VA, with a warm front/retreating wedge front delineating the northern extent of low-level moisture return. Instability should remain fairly weak through the period with northeastward extent from central/northern GA into the Carolinas. This limits confidence in thunderstorm intensities this afternoon. Still, a conditional threat for damaging wind gusts and perhaps a tornado or two exists with mainly linear convection that can develop/strengthen along the eastward-moving cold front this afternoon and evening. Late tonight, a low-topped line of convection may develop along the front from NC into southeastern VA and vicinity. While instability is forecast to remain minimal, strong flow at low/mid levels may still reach the surface through convective downdrafts. Have expanded the Marginal Risk for isolated damaging winds northward a bit based on this potential. Confidence in supercells developing across coastal/eastern NC in the last few hours of the period remains low. ..Gleason/Moore.. 11/21/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Tue Nov 21 2023 Valid 211630Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHERN/CENTRAL ALABAMA...THE FLORIDA PANHANDLE...AND SOUTHWESTERN GEORGIA... ...SUMMARY... A few tornadoes and isolated damaging gusts still appear possible today across parts of southern Alabama, southwestern Georgia, and the Florida Panhandle. Isolated damaging gusts and perhaps a tornado also remain possible this afternoon through tonight from central/northern Georgia into the Carolinas and southeastern Virginia. ...Synopsis... A large mid/upper-level cyclone over the Great Lakes this morning will continue to move eastward today. A trailing, positively tilted upper trough extends across the Midwest into the mid/lower MS Valley and southern Plains. The primary surface low over the Midwest is also forecast to develop slowly east-northeastward toward the Lower Great Lakes through tonight. A trailing cold front will progress eastward today and tonight across the Southeast and Mid-Atlantic states as a secondary surface low eventually forms over VA/MD and develops quickly northeastward across the coastal Mid-Atlantic. ...Central to Northeast Gulf Coast States... Swaths of warm-advection-related precipitation and widespread cloud cover have hindered daytime heating so far this morning across southern AL, the FL Panhandle, and GA. Still, some clearing has recently been noted between the cold front ongoing precipitation. Most guidance suggests that surface temperatures reaching into the low 70s will be needed for sufficient boundary-layer destabilization to support surface-based thunderstorms. Even with this modest heating, poor lapse rates aloft will likely hinder the degree of MLCAPE across the warm sector this afternoon. This should temper updraft intensities to some extent. But, latest VWPs from area radars show rather strong low-level and deep-layer shear are still present across this region. Any robust convection that can develop along/near the cold front this afternoon could become supercellular, with an associated threat for a few tornadoes and isolated damaging winds. But, confidence remains low that enough instability will develop to support intense thunderstorms. Have therefore maintained the low-confidence Slight Risk across this region with minimal changes. ...Georgia into the Carolinas and Southeastern Virginia... Widespread cloud cover and areas of precipitation remain prevalent from GA into the NC/SC and VA, with a warm front/retreating wedge front delineating the northern extent of low-level moisture return. Instability should remain fairly weak through the period with northeastward extent from central/northern GA into the Carolinas. This limits confidence in thunderstorm intensities this afternoon. Still, a conditional threat for damaging wind gusts and perhaps a tornado or two exists with mainly linear convection that can develop/strengthen along the eastward-moving cold front this afternoon and evening. Late tonight, a low-topped line of convection may develop along the front from NC into southeastern VA and vicinity. While instability is forecast to remain minimal, strong flow at low/mid levels may still reach the surface through convective downdrafts. Have expanded the Marginal Risk for isolated damaging winds northward a bit based on this potential. Confidence in supercells developing across coastal/eastern NC in the last few hours of the period remains low. ..Gleason/Moore.. 11/21/2023 Read more