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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0139 PM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO CRITICAL AREAS... The D2 Fire Weather Outlook remains on track with no updates needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0141 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are limited for Wednesday across the country. Broad upper ridging is expected to remain in place across the central CONUS through Wednesday. Embedded shortwave troughs propagating through the mean flow will likely result in some surface pressure falls and attendant wind responses across the northern High Plains and Great Lakes through the day, but overall wind speeds are expected to remain fairly benign (less than 20 mph based on recent ensemble guidance). Additionally, the maintenance of a southerly flow regime across the Plains will continue to foster weak moisture advection and reduce the potential for reaching elevated/critical RH criteria. One exception to this is central to southern WY, where the combination of modest lee troughing and a belt of 20-30 mph southwesterly mid-level flow should support areas of strong winds in the lee of terrain features. Downslope warming may allow for patchy elevated fire weather conditions, but mid and high-level cloud cover may offset the effects of compressional warming/drying and modulate diurnal RH reductions. ...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 0139 PM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO CRITICAL AREAS... The D2 Fire Weather Outlook remains on track with no updates needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0141 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are limited for Wednesday across the country. Broad upper ridging is expected to remain in place across the central CONUS through Wednesday. Embedded shortwave troughs propagating through the mean flow will likely result in some surface pressure falls and attendant wind responses across the northern High Plains and Great Lakes through the day, but overall wind speeds are expected to remain fairly benign (less than 20 mph based on recent ensemble guidance). Additionally, the maintenance of a southerly flow regime across the Plains will continue to foster weak moisture advection and reduce the potential for reaching elevated/critical RH criteria. One exception to this is central to southern WY, where the combination of modest lee troughing and a belt of 20-30 mph southwesterly mid-level flow should support areas of strong winds in the lee of terrain features. Downslope warming may allow for patchy elevated fire weather conditions, but mid and high-level cloud cover may offset the effects of compressional warming/drying and modulate diurnal RH reductions. ...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 1045 AM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the Lower 48 states on Wednesday. ...Synopsis... A slowly eastward-migrating mid-level trough over the Gulf of Mexico will favor shower and thunderstorm development mostly over the open Gulf waters. A surface low over the north-central Gulf will move little during the period. It cannot be ruled out that a few weak thunderstorms develop over the northern Gulf Coast, but the greater probabilities for isolated thunderstorms will be over FL Peninsula beginning during the day and spreading northward into Wednesday night. A split-flow regime over the West will feature a mid-level low over the eastern Pacific to the west of the CA coast. A gradual moistening in the low to mid levels will support pockets of weak buoyancy over the lower CO River Valley and Mojave Desert, mainly Wednesday night where a few lightning flashes are possible. ..Smith.. 11/14/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the Lower 48 states on Wednesday. ...Synopsis... A slowly eastward-migrating mid-level trough over the Gulf of Mexico will favor shower and thunderstorm development mostly over the open Gulf waters. A surface low over the north-central Gulf will move little during the period. It cannot be ruled out that a few weak thunderstorms develop over the northern Gulf Coast, but the greater probabilities for isolated thunderstorms will be over FL Peninsula beginning during the day and spreading northward into Wednesday night. A split-flow regime over the West will feature a mid-level low over the eastern Pacific to the west of the CA coast. A gradual moistening in the low to mid levels will support pockets of weak buoyancy over the lower CO River Valley and Mojave Desert, mainly Wednesday night where a few lightning flashes are possible. ..Smith.. 11/14/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the Lower 48 states on Wednesday. ...Synopsis... A slowly eastward-migrating mid-level trough over the Gulf of Mexico will favor shower and thunderstorm development mostly over the open Gulf waters. A surface low over the north-central Gulf will move little during the period. It cannot be ruled out that a few weak thunderstorms develop over the northern Gulf Coast, but the greater probabilities for isolated thunderstorms will be over FL Peninsula beginning during the day and spreading northward into Wednesday night. A split-flow regime over the West will feature a mid-level low over the eastern Pacific to the west of the CA coast. A gradual moistening in the low to mid levels will support pockets of weak buoyancy over the lower CO River Valley and Mojave Desert, mainly Wednesday night where a few lightning flashes are possible. ..Smith.. 11/14/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the Lower 48 states on Wednesday. ...Synopsis... A slowly eastward-migrating mid-level trough over the Gulf of Mexico will favor shower and thunderstorm development mostly over the open Gulf waters. A surface low over the north-central Gulf will move little during the period. It cannot be ruled out that a few weak thunderstorms develop over the northern Gulf Coast, but the greater probabilities for isolated thunderstorms will be over FL Peninsula beginning during the day and spreading northward into Wednesday night. A split-flow regime over the West will feature a mid-level low over the eastern Pacific to the west of the CA coast. A gradual moistening in the low to mid levels will support pockets of weak buoyancy over the lower CO River Valley and Mojave Desert, mainly Wednesday night where a few lightning flashes are possible. ..Smith.. 11/14/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Tue Nov 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the Lower 48 states on Wednesday. ...Synopsis... A slowly eastward-migrating mid-level trough over the Gulf of Mexico will favor shower and thunderstorm development mostly over the open Gulf waters. A surface low over the north-central Gulf will move little during the period. It cannot be ruled out that a few weak thunderstorms develop over the northern Gulf Coast, but the greater probabilities for isolated thunderstorms will be over FL Peninsula beginning during the day and spreading northward into Wednesday night. A split-flow regime over the West will feature a mid-level low over the eastern Pacific to the west of the CA coast. A gradual moistening in the low to mid levels will support pockets of weak buoyancy over the lower CO River Valley and Mojave Desert, mainly Wednesday night where a few lightning flashes are possible. ..Smith.. 11/14/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1041 AM CST Tue Nov 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook remains on track with no changes needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are expected to be limited for today across the country, though localized concerns may emerge across southeast WY and across the central Plains. Early-morning surface observations show a lee trough in place along the High Plains with southerly return flow ongoing through the southern to central Plains. This trough will migrate east into the central Plains through the day, maintain 15-25 mph southerly winds from KS into southwest MN. Although warm and breezy conditions are expected, returning moisture should limit RH reductions this afternoon. Ensemble guidance supports this idea with low probabilities for RH below 20%, even with a notable dry bias in some guidance (such as the HRRR/RAP). However, patchy areas of elevated conditions are possible across the Plains where RH can fall below 25%. Across southeast WY, 15-25 mph westerly downslope flow is expected during the morning to early afternoon hours, slowly abating through the mid/late afternoon as the surface trough exits the region. This timing of peak winds should be offset from the diurnal RH minimum, but a few hours of elevated conditions are possible around midday. The potentially limited duration of this threat precludes highlights, but trends will be monitored through the morning for lower than expected RH within the downslope flow regime. ...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 1041 AM CST Tue Nov 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook remains on track with no changes needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are expected to be limited for today across the country, though localized concerns may emerge across southeast WY and across the central Plains. Early-morning surface observations show a lee trough in place along the High Plains with southerly return flow ongoing through the southern to central Plains. This trough will migrate east into the central Plains through the day, maintain 15-25 mph southerly winds from KS into southwest MN. Although warm and breezy conditions are expected, returning moisture should limit RH reductions this afternoon. Ensemble guidance supports this idea with low probabilities for RH below 20%, even with a notable dry bias in some guidance (such as the HRRR/RAP). However, patchy areas of elevated conditions are possible across the Plains where RH can fall below 25%. Across southeast WY, 15-25 mph westerly downslope flow is expected during the morning to early afternoon hours, slowly abating through the mid/late afternoon as the surface trough exits the region. This timing of peak winds should be offset from the diurnal RH minimum, but a few hours of elevated conditions are possible around midday. The potentially limited duration of this threat precludes highlights, but trends will be monitored through the morning for lower than expected RH within the downslope flow regime. ...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 1041 AM CST Tue Nov 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook remains on track with no changes needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are expected to be limited for today across the country, though localized concerns may emerge across southeast WY and across the central Plains. Early-morning surface observations show a lee trough in place along the High Plains with southerly return flow ongoing through the southern to central Plains. This trough will migrate east into the central Plains through the day, maintain 15-25 mph southerly winds from KS into southwest MN. Although warm and breezy conditions are expected, returning moisture should limit RH reductions this afternoon. Ensemble guidance supports this idea with low probabilities for RH below 20%, even with a notable dry bias in some guidance (such as the HRRR/RAP). However, patchy areas of elevated conditions are possible across the Plains where RH can fall below 25%. Across southeast WY, 15-25 mph westerly downslope flow is expected during the morning to early afternoon hours, slowly abating through the mid/late afternoon as the surface trough exits the region. This timing of peak winds should be offset from the diurnal RH minimum, but a few hours of elevated conditions are possible around midday. The potentially limited duration of this threat precludes highlights, but trends will be monitored through the morning for lower than expected RH within the downslope flow regime. ...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 1041 AM CST Tue Nov 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook remains on track with no changes needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are expected to be limited for today across the country, though localized concerns may emerge across southeast WY and across the central Plains. Early-morning surface observations show a lee trough in place along the High Plains with southerly return flow ongoing through the southern to central Plains. This trough will migrate east into the central Plains through the day, maintain 15-25 mph southerly winds from KS into southwest MN. Although warm and breezy conditions are expected, returning moisture should limit RH reductions this afternoon. Ensemble guidance supports this idea with low probabilities for RH below 20%, even with a notable dry bias in some guidance (such as the HRRR/RAP). However, patchy areas of elevated conditions are possible across the Plains where RH can fall below 25%. Across southeast WY, 15-25 mph westerly downslope flow is expected during the morning to early afternoon hours, slowly abating through the mid/late afternoon as the surface trough exits the region. This timing of peak winds should be offset from the diurnal RH minimum, but a few hours of elevated conditions are possible around midday. The potentially limited duration of this threat precludes highlights, but trends will be monitored through the morning for lower than expected RH within the downslope flow regime. ...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 1041 AM CST Tue Nov 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook remains on track with no changes needed. See previous discussion for more information. ..Thornton.. 11/14/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Tue Nov 14 2023/ ...Synopsis... Fire weather concerns are expected to be limited for today across the country, though localized concerns may emerge across southeast WY and across the central Plains. Early-morning surface observations show a lee trough in place along the High Plains with southerly return flow ongoing through the southern to central Plains. This trough will migrate east into the central Plains through the day, maintain 15-25 mph southerly winds from KS into southwest MN. Although warm and breezy conditions are expected, returning moisture should limit RH reductions this afternoon. Ensemble guidance supports this idea with low probabilities for RH below 20%, even with a notable dry bias in some guidance (such as the HRRR/RAP). However, patchy areas of elevated conditions are possible across the Plains where RH can fall below 25%. Across southeast WY, 15-25 mph westerly downslope flow is expected during the morning to early afternoon hours, slowly abating through the mid/late afternoon as the surface trough exits the region. This timing of peak winds should be offset from the diurnal RH minimum, but a few hours of elevated conditions are possible around midday. The potentially limited duration of this threat precludes highlights, but trends will be monitored through the morning for lower than expected RH within the downslope flow regime. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Tue Nov 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across southern into central Florida. ...Synopsis... Broad upper ridging will remain in place across much of the central and southern CONUS as multiple mid-level impulses traverse the ridge over the northern U.S. today. Surface high pressure will continue to overspread most of the CONUS, with large-scale subsidence limiting thunderstorm potential over most locales. The one exception will be portions of the Gulf Coast and the central/southern FL Peninsula. A mid-level trough and accompanying surface cyclone over the northern Gulf of Mexico will continue to shunt eastward through the period, promoting enough moisture advection and deep-layer ascent across the central Gulf Coast and central/southern FL Peninsula to support at least isolated thunderstorm development today into tonight. ..Squitieri.. 11/14/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Tue Nov 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across southern into central Florida. ...Synopsis... Broad upper ridging will remain in place across much of the central and southern CONUS as multiple mid-level impulses traverse the ridge over the northern U.S. today. Surface high pressure will continue to overspread most of the CONUS, with large-scale subsidence limiting thunderstorm potential over most locales. The one exception will be portions of the Gulf Coast and the central/southern FL Peninsula. A mid-level trough and accompanying surface cyclone over the northern Gulf of Mexico will continue to shunt eastward through the period, promoting enough moisture advection and deep-layer ascent across the central Gulf Coast and central/southern FL Peninsula to support at least isolated thunderstorm development today into tonight. ..Squitieri.. 11/14/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Tue Nov 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across southern into central Florida. ...Synopsis... Broad upper ridging will remain in place across much of the central and southern CONUS as multiple mid-level impulses traverse the ridge over the northern U.S. today. Surface high pressure will continue to overspread most of the CONUS, with large-scale subsidence limiting thunderstorm potential over most locales. The one exception will be portions of the Gulf Coast and the central/southern FL Peninsula. A mid-level trough and accompanying surface cyclone over the northern Gulf of Mexico will continue to shunt eastward through the period, promoting enough moisture advection and deep-layer ascent across the central Gulf Coast and central/southern FL Peninsula to support at least isolated thunderstorm development today into tonight. ..Squitieri.. 11/14/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Tue Nov 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across southern into central Florida. ...Synopsis... Broad upper ridging will remain in place across much of the central and southern CONUS as multiple mid-level impulses traverse the ridge over the northern U.S. today. Surface high pressure will continue to overspread most of the CONUS, with large-scale subsidence limiting thunderstorm potential over most locales. The one exception will be portions of the Gulf Coast and the central/southern FL Peninsula. A mid-level trough and accompanying surface cyclone over the northern Gulf of Mexico will continue to shunt eastward through the period, promoting enough moisture advection and deep-layer ascent across the central Gulf Coast and central/southern FL Peninsula to support at least isolated thunderstorm development today into tonight. ..Squitieri.. 11/14/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Tue Nov 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across southern into central Florida. ...Synopsis... Broad upper ridging will remain in place across much of the central and southern CONUS as multiple mid-level impulses traverse the ridge over the northern U.S. today. Surface high pressure will continue to overspread most of the CONUS, with large-scale subsidence limiting thunderstorm potential over most locales. The one exception will be portions of the Gulf Coast and the central/southern FL Peninsula. A mid-level trough and accompanying surface cyclone over the northern Gulf of Mexico will continue to shunt eastward through the period, promoting enough moisture advection and deep-layer ascent across the central Gulf Coast and central/southern FL Peninsula to support at least isolated thunderstorm development today into tonight. ..Squitieri.. 11/14/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 AM CST Tue Nov 14 2023 Valid 141300Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across south Florida. ...Synopsis/Discussion... In mid/upper levels, a split-flow pattern will be maintained around a quasistationary cyclone offshore from the Pacific Coast, with downstream ridging across portions of the Great Basin and southern Rockies. Farther east, a southern-stream shortwave trough -- evident in moisture-channel imagery from east TX to the lower TX Coast -- will move eastward to the central Gulf coast and central Gulf of Mexico by the end of the period. A related frontal-wave low was analyzed at 11Z over Gulf waters roughly south of ARA and east of BRO, with cold front southwestward over northeastern MX. A warm front was drawn to about 75-80 nm south of the Mississippi River mouth, then southeastward over the east-central Gulf, becoming quasistationary across south FL and through a weak wave low near MIA. The Gulf low is forecast to deepen and drift northeastward through the period, as the mid/upper trough approaches. By 12Z, the low should be over or just south of the Mississippi River mouth, but with the warm sector over water, as the warm-frontal segment arches eastward then southeastward over the north-central/eastern Gulf. The front should move little over south FL, perhaps with a slight northward drift. The cold front will move slowly eastward over the western/central Gulf south of the low. Isolated and marginal thunder potential exists over land beneath an elevated warm-advection/moisture-transport conveyor, located north through northeast of the Gulf low. Marginal buoyancy is expected, with elevated MUCAPE generally less than 300 J/kg and just sporadically reaching ideal icing layers for lightning generation. Isolated thunderstorms also may be embedded in deep low-level easterlies across southern portions of the FL Peninsula, near the warm/stationary frontal zone. Organized severe potential appears minimal due to lack of greater magnitudes of lift, lapse rates and deep shear. The bulk of thunderstorms and any appreciable strong- severe convective potential should remain over open Gulf waters, where stronger shear is forecast, and air-sea fluxes of heat and moisture will optimize boundary-layer theta-e for surface-based effective inflow. ..Edwards/Gleason.. 11/14/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 AM CST Tue Nov 14 2023 Valid 141300Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across south Florida. ...Synopsis/Discussion... In mid/upper levels, a split-flow pattern will be maintained around a quasistationary cyclone offshore from the Pacific Coast, with downstream ridging across portions of the Great Basin and southern Rockies. Farther east, a southern-stream shortwave trough -- evident in moisture-channel imagery from east TX to the lower TX Coast -- will move eastward to the central Gulf coast and central Gulf of Mexico by the end of the period. A related frontal-wave low was analyzed at 11Z over Gulf waters roughly south of ARA and east of BRO, with cold front southwestward over northeastern MX. A warm front was drawn to about 75-80 nm south of the Mississippi River mouth, then southeastward over the east-central Gulf, becoming quasistationary across south FL and through a weak wave low near MIA. The Gulf low is forecast to deepen and drift northeastward through the period, as the mid/upper trough approaches. By 12Z, the low should be over or just south of the Mississippi River mouth, but with the warm sector over water, as the warm-frontal segment arches eastward then southeastward over the north-central/eastern Gulf. The front should move little over south FL, perhaps with a slight northward drift. The cold front will move slowly eastward over the western/central Gulf south of the low. Isolated and marginal thunder potential exists over land beneath an elevated warm-advection/moisture-transport conveyor, located north through northeast of the Gulf low. Marginal buoyancy is expected, with elevated MUCAPE generally less than 300 J/kg and just sporadically reaching ideal icing layers for lightning generation. Isolated thunderstorms also may be embedded in deep low-level easterlies across southern portions of the FL Peninsula, near the warm/stationary frontal zone. Organized severe potential appears minimal due to lack of greater magnitudes of lift, lapse rates and deep shear. The bulk of thunderstorms and any appreciable strong- severe convective potential should remain over open Gulf waters, where stronger shear is forecast, and air-sea fluxes of heat and moisture will optimize boundary-layer theta-e for surface-based effective inflow. ..Edwards/Gleason.. 11/14/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 AM CST Tue Nov 14 2023 Valid 141300Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible along part of the central Gulf Coast and across south Florida. ...Synopsis/Discussion... In mid/upper levels, a split-flow pattern will be maintained around a quasistationary cyclone offshore from the Pacific Coast, with downstream ridging across portions of the Great Basin and southern Rockies. Farther east, a southern-stream shortwave trough -- evident in moisture-channel imagery from east TX to the lower TX Coast -- will move eastward to the central Gulf coast and central Gulf of Mexico by the end of the period. A related frontal-wave low was analyzed at 11Z over Gulf waters roughly south of ARA and east of BRO, with cold front southwestward over northeastern MX. A warm front was drawn to about 75-80 nm south of the Mississippi River mouth, then southeastward over the east-central Gulf, becoming quasistationary across south FL and through a weak wave low near MIA. The Gulf low is forecast to deepen and drift northeastward through the period, as the mid/upper trough approaches. By 12Z, the low should be over or just south of the Mississippi River mouth, but with the warm sector over water, as the warm-frontal segment arches eastward then southeastward over the north-central/eastern Gulf. The front should move little over south FL, perhaps with a slight northward drift. The cold front will move slowly eastward over the western/central Gulf south of the low. Isolated and marginal thunder potential exists over land beneath an elevated warm-advection/moisture-transport conveyor, located north through northeast of the Gulf low. Marginal buoyancy is expected, with elevated MUCAPE generally less than 300 J/kg and just sporadically reaching ideal icing layers for lightning generation. Isolated thunderstorms also may be embedded in deep low-level easterlies across southern portions of the FL Peninsula, near the warm/stationary frontal zone. Organized severe potential appears minimal due to lack of greater magnitudes of lift, lapse rates and deep shear. The bulk of thunderstorms and any appreciable strong- severe convective potential should remain over open Gulf waters, where stronger shear is forecast, and air-sea fluxes of heat and moisture will optimize boundary-layer theta-e for surface-based effective inflow. ..Edwards/Gleason.. 11/14/2023 Read more