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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few non-severe thunderstorms are possible over parts of the Mid Atlantic during the day on Wednesday. ...Synopsis and Discussion... A deep upper low will fill slightly as it moves slowly east across the lower MS Valley, with a large area of cyclonic flow aloft over the Plains, MS Valley and Southeast. Relatively cool air will remain over much of the Plains with northerly winds extending into the western Gulf of Mexico, but a weak surface low will develop over NC in a zone of warm southeasterlies well ahead of the upper low. Extensive clouds and precipitation will limit destabilization as well as low-level lapse rates over NC and southern VA where MUCAPE may approach 500 J/kg. However, this will be sufficient to support scattered convection within the larger area of precipitation, by virtue of cool midlevel temperatures and mainly early in the day prior to drier air pushing in from the west as 850 mb winds veer. While forecast soundings over NC do show surface-based parcel potential, real boundary-layer buoyancy will be limited by the poor lapse rates/saturated profiles in a weak forcing regime. Therefore, despite veering winds with height and effective SRH values of 200-300 m2/s2, severe weather remains unlikely. ..Jewell.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 261630Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A large, mature mid-latitude cyclone is centered over the eastern NE/KS border vicinity. This cyclone is expected to move gradually into MO, while becoming increasingly vertically stacked with time. Cold and dry air mass associated with this cyclone will dominant the sensible weather across much of the CONUS. The only exception is from the coastal Southeast through the Mid-Atlantic States. Here, an extensive warm conveyor, originating over central Mexico and the western Gulf of Mexico and splitting over the Mid-Atlantic, will contribute to broad isentropic ascent. Strongest ascent is ongoing over the SC vicinity, where enhanced low-level southeasterly flow is augmenting the modest ascent within the warm conveyor. This low-level flow is forecast to continue throughout the period while gradually shifting northward, resulting in prolonged isentropic ascent and a continued threat for isolated thunderstorms embedded within the broader precipitation shield. Highest thunderstorm coverage is expected over the western Carolinas. Some favorable low-level shear may exist across the central/eastern Carolinas, but this shear should be displaced west of any surface-based buoyancy, limiting the severe potential. ..Mosier/Thornton.. 12/26/2023 Read more

MD 2349 CONCERNING FREEZING RAIN FOR MUCH OF EASTERN NORTH DAKOTA...NORTH-CENTRAL SOUTH DAKOTA
Mesoscale Discussion 2349 NWS Storm Prediction Center Norman OK 0527 AM CST Tue Dec 26 2023 Areas affected...much of eastern North Dakota...north-central South Dakota Concerning...Freezing rain Valid 261127Z - 261630Z SUMMARY...Freezing rain, mixed occasionally with sleet, should continue across much of the discussion area through mid morning. Ice accumulations may exceed 0.05 inches/3 hours. DISCUSSION...An area of freezing rain, mixed at times with sleet, continues across the discussion area as of 1120z. The precipitation is supported by ample warm/moist advection and large-scale ascent associated with lobes of vorticity rotating around the expansive central Plains cyclone. Latest short-term deterministic and ensemble guidance reflects high probabilities of freezing rain continuing as the dominant precip type through mid morning. This is supported by RAP-based forecast soundings generally showing a warm nose between 900 and 800 mb where surface wet bulb temperatures are below freezing. Continued low- and mid-level moisture transport should result in freezing rain accumulations in excess of 0.05 inches/3 hours in many areas through 15z. ..Bunting.. 12/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...ABR...BIS... LAT...LON 46249768 44709964 45240064 46470041 47549918 47729865 47969766 47839695 47299692 46249768 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1018 AM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CST Tue Dec 26 2023/ ...Synopsis... On Wednesday, a closed upper low will drift slowly east across the Midwest. By this time, the surface low will weaken enough that stronger winds mostly should subside. Fuels should remain moist across most of the CONUS on Wednesday with cool conditions across most of the western/central CONUS and mild, but moist conditions along the East Coast. Therefore, fire weather concerns will remain minimal. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...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 1017 AM CST Tue Dec 26 2023 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... Morning water vapor loops indicate a well-defined dry conveyor belt overspreading the southern High Plains, which is associated with an expansive midlevel cyclone over the central CONUS. Strong west-northwesterly flow aloft associated with this feature, coupled with a modest pressure gradient, will favor 20-25 mph sustained west-northwesterly surface winds (with gusts upwards of 35 mph) from southeast NM into the TX Trans-Pecos. Here, downslope warming/drying and boundary-layer mixing into the deep layer of dry air will contribute to 10-15 percent minimum RH this afternoon. While the area did receive some precipitation this past weekend, freeze-cured grasses may still support locally elevated fire-weather conditions given a day or two of drying and the dry/breezy conditions. ..Weinman.. 12/26/2023 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Dec 26 2023/ ...Synopsis... Some breezy conditions are possible today across the central/northern Plains as the surface pressure gradient slowly relaxes. However, cool conditions dominate across most of the CONUS. In addition, most of the CONUS has seen wetting rain within the last few days. Therefore, fire weather concerns are minimal today. ...Please see www.spc.noaa.gov/fire for graphic product... Read more