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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1016 AM CST Wed Nov 20 2024 Valid 201700Z - 211200Z ...Central Plains... The previous forecast remains on track with only minor adjustments made based on recent observations and trends in forecast guidance. Gradient winds gusting to 40-50 mph are already being observed across southern SD and will spread into NE by late morning as a shallow nocturnal inversion (evident on the 12z LBF sounding) mixes out. The greatest fire threat should be focused across southwest SD into western NE where fuels are driest, but elevated to critical fire weather conditions will likely spread into south-central NE as well. However, recent 1+ inch rainfall amounts within the past 24 hours should limit fire potential with eastward extent. ...Western to central Nevada... Localized elevated to critical fire weather conditions are ongoing this morning across far western NV within the downslope wind regime in the lee of the central Sierra Nevada. Such conditions should gradually become more widespread into central NV by late afternoon as diurnal heating promotes drying/mixing. Despite the wind/RH conditions, recent fuel guidance suggests ERCs remain below critical thresholds to warrant risk highlights. ..Moore.. 11/20/2024 .PREV DISCUSSION... /ISSUED 1141 PM CST Tue Nov 19 2024/ ...Synopsis... An upper-level low initially in the northern Plains will shift eastward into the Upper Midwest and intensify today. Strong low to mid-level winds will continue across portions of the central Plains as an associated surface low deepens in the Lower Great Lakes region. ...Central Plains... Temperatures will again be rather cool (mid/upper 40s F appear most probable). However, strong surface winds of 15-25 mph (with higher gusts) are likely across parts of eastern Wyoming into adjacent South Dakota and western Nebraska. RH will also fall to near 20% given the very dry airmass. Some fire weather concern could develop in fine fuels. Some weakening of the pressure gradient is expected by late afternoon which will limit the duration of the threat. ...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 1016 AM CST Wed Nov 20 2024 Valid 201700Z - 211200Z ...Central Plains... The previous forecast remains on track with only minor adjustments made based on recent observations and trends in forecast guidance. Gradient winds gusting to 40-50 mph are already being observed across southern SD and will spread into NE by late morning as a shallow nocturnal inversion (evident on the 12z LBF sounding) mixes out. The greatest fire threat should be focused across southwest SD into western NE where fuels are driest, but elevated to critical fire weather conditions will likely spread into south-central NE as well. However, recent 1+ inch rainfall amounts within the past 24 hours should limit fire potential with eastward extent. ...Western to central Nevada... Localized elevated to critical fire weather conditions are ongoing this morning across far western NV within the downslope wind regime in the lee of the central Sierra Nevada. Such conditions should gradually become more widespread into central NV by late afternoon as diurnal heating promotes drying/mixing. Despite the wind/RH conditions, recent fuel guidance suggests ERCs remain below critical thresholds to warrant risk highlights. ..Moore.. 11/20/2024 .PREV DISCUSSION... /ISSUED 1141 PM CST Tue Nov 19 2024/ ...Synopsis... An upper-level low initially in the northern Plains will shift eastward into the Upper Midwest and intensify today. Strong low to mid-level winds will continue across portions of the central Plains as an associated surface low deepens in the Lower Great Lakes region. ...Central Plains... Temperatures will again be rather cool (mid/upper 40s F appear most probable). However, strong surface winds of 15-25 mph (with higher gusts) are likely across parts of eastern Wyoming into adjacent South Dakota and western Nebraska. RH will also fall to near 20% given the very dry airmass. Some fire weather concern could develop in fine fuels. Some weakening of the pressure gradient is expected by late afternoon which will limit the duration of the threat. ...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 1016 AM CST Wed Nov 20 2024 Valid 201700Z - 211200Z ...Central Plains... The previous forecast remains on track with only minor adjustments made based on recent observations and trends in forecast guidance. Gradient winds gusting to 40-50 mph are already being observed across southern SD and will spread into NE by late morning as a shallow nocturnal inversion (evident on the 12z LBF sounding) mixes out. The greatest fire threat should be focused across southwest SD into western NE where fuels are driest, but elevated to critical fire weather conditions will likely spread into south-central NE as well. However, recent 1+ inch rainfall amounts within the past 24 hours should limit fire potential with eastward extent. ...Western to central Nevada... Localized elevated to critical fire weather conditions are ongoing this morning across far western NV within the downslope wind regime in the lee of the central Sierra Nevada. Such conditions should gradually become more widespread into central NV by late afternoon as diurnal heating promotes drying/mixing. Despite the wind/RH conditions, recent fuel guidance suggests ERCs remain below critical thresholds to warrant risk highlights. ..Moore.. 11/20/2024 .PREV DISCUSSION... /ISSUED 1141 PM CST Tue Nov 19 2024/ ...Synopsis... An upper-level low initially in the northern Plains will shift eastward into the Upper Midwest and intensify today. Strong low to mid-level winds will continue across portions of the central Plains as an associated surface low deepens in the Lower Great Lakes region. ...Central Plains... Temperatures will again be rather cool (mid/upper 40s F appear most probable). However, strong surface winds of 15-25 mph (with higher gusts) are likely across parts of eastern Wyoming into adjacent South Dakota and western Nebraska. RH will also fall to near 20% given the very dry airmass. Some fire weather concern could develop in fine fuels. Some weakening of the pressure gradient is expected by late afternoon which will limit the duration of the threat. ...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 1016 AM CST Wed Nov 20 2024 Valid 201700Z - 211200Z ...Central Plains... The previous forecast remains on track with only minor adjustments made based on recent observations and trends in forecast guidance. Gradient winds gusting to 40-50 mph are already being observed across southern SD and will spread into NE by late morning as a shallow nocturnal inversion (evident on the 12z LBF sounding) mixes out. The greatest fire threat should be focused across southwest SD into western NE where fuels are driest, but elevated to critical fire weather conditions will likely spread into south-central NE as well. However, recent 1+ inch rainfall amounts within the past 24 hours should limit fire potential with eastward extent. ...Western to central Nevada... Localized elevated to critical fire weather conditions are ongoing this morning across far western NV within the downslope wind regime in the lee of the central Sierra Nevada. Such conditions should gradually become more widespread into central NV by late afternoon as diurnal heating promotes drying/mixing. Despite the wind/RH conditions, recent fuel guidance suggests ERCs remain below critical thresholds to warrant risk highlights. ..Moore.. 11/20/2024 .PREV DISCUSSION... /ISSUED 1141 PM CST Tue Nov 19 2024/ ...Synopsis... An upper-level low initially in the northern Plains will shift eastward into the Upper Midwest and intensify today. Strong low to mid-level winds will continue across portions of the central Plains as an associated surface low deepens in the Lower Great Lakes region. ...Central Plains... Temperatures will again be rather cool (mid/upper 40s F appear most probable). However, strong surface winds of 15-25 mph (with higher gusts) are likely across parts of eastern Wyoming into adjacent South Dakota and western Nebraska. RH will also fall to near 20% given the very dry airmass. Some fire weather concern could develop in fine fuels. Some weakening of the pressure gradient is expected by late afternoon which will limit the duration of the threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 AM CST Wed Nov 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely today and tonight. ...Mid-Atlantic into North Carolina... An occluded cyclone over the Upper Midwest this morning will evolve eastward across the Great Lakes through tonight. A related strong mid/upper-level jet will overspread the OH Valley into the Mid-Atlantic and Carolinas through the day, as a surface cold front also advances eastward over these regions. While low-level moisture will gradually increase across NC into the southern Mid-Atlantic by early evening, poor lapse rates and limited daytime heating should hinder the development of any more than weak instability. Still, low-topped showers should still form along or just ahead of the cold front across eastern OH into western PA and WV by late this afternoon. It remains unclear whether this convection will become deep enough to foster lightning flashes, but enhanced low/mid-level flow could still support some chance for gusty winds with this activity. This elevated convection is forecast to continue moving eastward over the southern Mid-Atlantic this evening and overnight. However, boundary-layer instability is forecast to remain minimal with eastward extent, which should limit the overall severe threat. ...Coastal Pacific Northwest... A powerful upper cyclone off the coast of British Columbia should continue to occlude today as it moves slowly away from the coast. In the meantime, ascent associated with low-level warm advection and a strong southwesterly mid/upper-level jet is supporting low-topped convection this morning across coastal portions of the Pacific Northwest. With surface dewpoints generally in the low to mid 40s over land, instability will remain very limited (reference negligible MUCAPE from 12Z observed soundings at UIL/SLE). Still, some chance strong/gusty winds may exist with the ongoing convection moving onshore given the strength of the low/mid-level flow (see recent VWPs from KLGX). But, the scant instability should preclude organized severe thunderstorms across coastal WA/OR today. ...Florida... Convection over the eastern Gulf of Mexico has generally weakened as it approaches the FL Gulf Coast and Keys early this morning. The potential for appreciable destabilization over land today should remain limited ahead of a cold front. While isolated lighting flashes may still occur along/near the coast and parts of the Keys, better thunderstorm potential will probably remain offshore from the FL Peninsula. ..Gleason/Kerr.. 11/20/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0305 AM CST Wed Nov 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... An upper trough will move out of the northeastern states from Sat/D4 into Sun/D5, with the ridge flattening over the Plains. This will result in a broad belt of near zonal flow across much of the CONUS, with perhaps a slight propensity for cyclonic height curvature over the Great Lakes into eastern Canada. Low-level moisture return will occur gradually, especially from Mon/D6 onward when 60s dewpoints may extend from eastern TX into the lower MS Valley. However, not until around Tue Night/D7 do most models show any appreciable instability, and even then it will likely be weak. As such, severe storms are not forecast. However, a few strong storms cannot be ruled out by around Wed/D8 due to several days of persistent moistening, especially if a shortwave trough can amplify within the strong flow regime. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Nov 20 2024 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm activity will remain quite limited on Friday. ...Synopsis... A deep upper low will begin centered over the PA/NY area, but within a large, deep upper trough. Meanwhile, an upper ridge will exist over the Rockies, shifting slowly east toward the High Plains by 12Z Saturday. West of this ridge, height falls will occur over the Pacific Northwest as a broad upper trough moves in. High pressure will persist over much of the CONUS, the exception being over the Northeast near the deep tropospheric cyclone, with a dry air mass lacking of CAPE. The exception will be just off the WA/OR coasts, where low-topped convection is possible over the ocean, and perhaps near the coastline by 12Z Saturday. ..Jewell.. 11/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Nov 20 2024 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm activity will remain quite limited on Friday. ...Synopsis... A deep upper low will begin centered over the PA/NY area, but within a large, deep upper trough. Meanwhile, an upper ridge will exist over the Rockies, shifting slowly east toward the High Plains by 12Z Saturday. West of this ridge, height falls will occur over the Pacific Northwest as a broad upper trough moves in. High pressure will persist over much of the CONUS, the exception being over the Northeast near the deep tropospheric cyclone, with a dry air mass lacking of CAPE. The exception will be just off the WA/OR coasts, where low-topped convection is possible over the ocean, and perhaps near the coastline by 12Z Saturday. ..Jewell.. 11/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Nov 20 2024 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm activity will remain quite limited on Friday. ...Synopsis... A deep upper low will begin centered over the PA/NY area, but within a large, deep upper trough. Meanwhile, an upper ridge will exist over the Rockies, shifting slowly east toward the High Plains by 12Z Saturday. West of this ridge, height falls will occur over the Pacific Northwest as a broad upper trough moves in. High pressure will persist over much of the CONUS, the exception being over the Northeast near the deep tropospheric cyclone, with a dry air mass lacking of CAPE. The exception will be just off the WA/OR coasts, where low-topped convection is possible over the ocean, and perhaps near the coastline by 12Z Saturday. ..Jewell.. 11/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Nov 20 2024 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm activity will remain quite limited on Friday. ...Synopsis... A deep upper low will begin centered over the PA/NY area, but within a large, deep upper trough. Meanwhile, an upper ridge will exist over the Rockies, shifting slowly east toward the High Plains by 12Z Saturday. West of this ridge, height falls will occur over the Pacific Northwest as a broad upper trough moves in. High pressure will persist over much of the CONUS, the exception being over the Northeast near the deep tropospheric cyclone, with a dry air mass lacking of CAPE. The exception will be just off the WA/OR coasts, where low-topped convection is possible over the ocean, and perhaps near the coastline by 12Z Saturday. ..Jewell.. 11/20/2024 Read more