Aggregator

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 PM CST Wed Dec 27 2023 Valid 280100Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...01Z Update... Even with instability forecast to remain rather weak, isolated lighting flashes will remain possible within a band of precipitation that will move eastward across the coastal Mid-Atlantic tonight. Occasional thunderstorms may also occur late tonight into early Thursday morning across parts of the FL Keys as modest low-level moisture return occurs in tandem with a low-amplitude shortwave trough moving northeastward across the Gulf of Mexico. Isolated convection capable of producing lightning flashes will also remain possible this evening over parts of CA and coastal WA/OR. Across all these regions, weak instability will preclude a threat for organized severe thunderstorms. ..Gleason.. 12/28/2023 Read more

No watches are valid as of Wed Dec 27 22:17:01 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Dec 27 22:17:01 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0322 PM CST Wed Dec 27 2023 Valid 291200Z - 041200Z The potential for critical fire-weather conditions appears low through the extended forecast period. On D3/Friday, a midlevel low will devolve into a large-scale trough over the eastern CONUS, while a related swath of strong deep-layer west-southwesterly flow overspreads the Southeast. This may promote locally breezy conditions across the region, though cool surface temperatures/marginal RH reductions and recent rainfall should limit most fire-weather concerns. Thereafter, a large-scale trough over the West will deamplify into a shortwave trough and cross the southern Rockies on D5/Sunday. As this occurs, an accompanying belt of strong westerly downslope flow will promote lee troughing over the southern High Plains, with dry/breezy conditions possible across portions of West TX. With that said, marginal fuels across the area should mitigate the fire-weather threat. ..Weinman.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0322 PM CST Wed Dec 27 2023 Valid 291200Z - 041200Z The potential for critical fire-weather conditions appears low through the extended forecast period. On D3/Friday, a midlevel low will devolve into a large-scale trough over the eastern CONUS, while a related swath of strong deep-layer west-southwesterly flow overspreads the Southeast. This may promote locally breezy conditions across the region, though cool surface temperatures/marginal RH reductions and recent rainfall should limit most fire-weather concerns. Thereafter, a large-scale trough over the West will deamplify into a shortwave trough and cross the southern Rockies on D5/Sunday. As this occurs, an accompanying belt of strong westerly downslope flow will promote lee troughing over the southern High Plains, with dry/breezy conditions possible across portions of West TX. With that said, marginal fuels across the area should mitigate the fire-weather threat. ..Weinman.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0322 PM CST Wed Dec 27 2023 Valid 291200Z - 041200Z The potential for critical fire-weather conditions appears low through the extended forecast period. On D3/Friday, a midlevel low will devolve into a large-scale trough over the eastern CONUS, while a related swath of strong deep-layer west-southwesterly flow overspreads the Southeast. This may promote locally breezy conditions across the region, though cool surface temperatures/marginal RH reductions and recent rainfall should limit most fire-weather concerns. Thereafter, a large-scale trough over the West will deamplify into a shortwave trough and cross the southern Rockies on D5/Sunday. As this occurs, an accompanying belt of strong westerly downslope flow will promote lee troughing over the southern High Plains, with dry/breezy conditions possible across portions of West TX. With that said, marginal fuels across the area should mitigate the fire-weather threat. ..Weinman.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0322 PM CST Wed Dec 27 2023 Valid 291200Z - 041200Z The potential for critical fire-weather conditions appears low through the extended forecast period. On D3/Friday, a midlevel low will devolve into a large-scale trough over the eastern CONUS, while a related swath of strong deep-layer west-southwesterly flow overspreads the Southeast. This may promote locally breezy conditions across the region, though cool surface temperatures/marginal RH reductions and recent rainfall should limit most fire-weather concerns. Thereafter, a large-scale trough over the West will deamplify into a shortwave trough and cross the southern Rockies on D5/Sunday. As this occurs, an accompanying belt of strong westerly downslope flow will promote lee troughing over the southern High Plains, with dry/breezy conditions possible across portions of West TX. With that said, marginal fuels across the area should mitigate the fire-weather threat. ..Weinman.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0322 PM CST Wed Dec 27 2023 Valid 291200Z - 041200Z The potential for critical fire-weather conditions appears low through the extended forecast period. On D3/Friday, a midlevel low will devolve into a large-scale trough over the eastern CONUS, while a related swath of strong deep-layer west-southwesterly flow overspreads the Southeast. This may promote locally breezy conditions across the region, though cool surface temperatures/marginal RH reductions and recent rainfall should limit most fire-weather concerns. Thereafter, a large-scale trough over the West will deamplify into a shortwave trough and cross the southern Rockies on D5/Sunday. As this occurs, an accompanying belt of strong westerly downslope flow will promote lee troughing over the southern High Plains, with dry/breezy conditions possible across portions of West TX. With that said, marginal fuels across the area should mitigate the fire-weather threat. ..Weinman.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0132 PM CST Wed Dec 27 2023 Valid 272000Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. Only minor changes to the Carolinas thunder line as drier air moves in from the southwest. ..Jewell.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Wed Dec 27 2023/ ...Mid Atlantic Region... A large upper low remains dominant over the central/eastern CONUS, with a deep warm-conveyor regime over the Mid-Atlantic region. Scattered showers and isolated thunderstorms will be possible this afternoon from eastern NC northward across the Chesapeake Bay area into PA/NJ. A cool and marginally unstable boundary-layer will preclude a risk of severe storms. ...FL Keys... A southern-stream shortwave trough over northern Mexico will track across the Gulf of Mexico and begin affecting the FL Keys after midnight. This may result in isolated thunderstorms over the lower Keys or nearby shelf waters. ...West Coast... A few lightning flashes are possible this afternoon and evening over coastal WA/OR and parts of northern/central CA as a cold front moves ashore. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0132 PM CST Wed Dec 27 2023 Valid 272000Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. Only minor changes to the Carolinas thunder line as drier air moves in from the southwest. ..Jewell.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Wed Dec 27 2023/ ...Mid Atlantic Region... A large upper low remains dominant over the central/eastern CONUS, with a deep warm-conveyor regime over the Mid-Atlantic region. Scattered showers and isolated thunderstorms will be possible this afternoon from eastern NC northward across the Chesapeake Bay area into PA/NJ. A cool and marginally unstable boundary-layer will preclude a risk of severe storms. ...FL Keys... A southern-stream shortwave trough over northern Mexico will track across the Gulf of Mexico and begin affecting the FL Keys after midnight. This may result in isolated thunderstorms over the lower Keys or nearby shelf waters. ...West Coast... A few lightning flashes are possible this afternoon and evening over coastal WA/OR and parts of northern/central CA as a cold front moves ashore. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0132 PM CST Wed Dec 27 2023 Valid 272000Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. Only minor changes to the Carolinas thunder line as drier air moves in from the southwest. ..Jewell.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Wed Dec 27 2023/ ...Mid Atlantic Region... A large upper low remains dominant over the central/eastern CONUS, with a deep warm-conveyor regime over the Mid-Atlantic region. Scattered showers and isolated thunderstorms will be possible this afternoon from eastern NC northward across the Chesapeake Bay area into PA/NJ. A cool and marginally unstable boundary-layer will preclude a risk of severe storms. ...FL Keys... A southern-stream shortwave trough over northern Mexico will track across the Gulf of Mexico and begin affecting the FL Keys after midnight. This may result in isolated thunderstorms over the lower Keys or nearby shelf waters. ...West Coast... A few lightning flashes are possible this afternoon and evening over coastal WA/OR and parts of northern/central CA as a cold front moves ashore. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0132 PM CST Wed Dec 27 2023 Valid 272000Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. Only minor changes to the Carolinas thunder line as drier air moves in from the southwest. ..Jewell.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Wed Dec 27 2023/ ...Mid Atlantic Region... A large upper low remains dominant over the central/eastern CONUS, with a deep warm-conveyor regime over the Mid-Atlantic region. Scattered showers and isolated thunderstorms will be possible this afternoon from eastern NC northward across the Chesapeake Bay area into PA/NJ. A cool and marginally unstable boundary-layer will preclude a risk of severe storms. ...FL Keys... A southern-stream shortwave trough over northern Mexico will track across the Gulf of Mexico and begin affecting the FL Keys after midnight. This may result in isolated thunderstorms over the lower Keys or nearby shelf waters. ...West Coast... A few lightning flashes are possible this afternoon and evening over coastal WA/OR and parts of northern/central CA as a cold front moves ashore. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0133 PM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1241 AM CST Wed Dec 27 2023/ ...Synopsis... Cool temperatures and moist fuels across most of the CONUS will limit fire weather concerns on Thursday, as a closed upper low slowly drifts east across the Ohio Valley. ...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 0133 PM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1241 AM CST Wed Dec 27 2023/ ...Synopsis... Cool temperatures and moist fuels across most of the CONUS will limit fire weather concerns on Thursday, as a closed upper low slowly drifts east across the Ohio Valley. ...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 0133 PM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1241 AM CST Wed Dec 27 2023/ ...Synopsis... Cool temperatures and moist fuels across most of the CONUS will limit fire weather concerns on Thursday, as a closed upper low slowly drifts east across the Ohio Valley. ...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 0133 PM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1241 AM CST Wed Dec 27 2023/ ...Synopsis... Cool temperatures and moist fuels across most of the CONUS will limit fire weather concerns on Thursday, as a closed upper low slowly drifts east across the Ohio Valley. ...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 0133 PM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... The forecast remains on track. For details, see the previous discussion below. ..Weinman.. 12/27/2023 .PREV DISCUSSION... /ISSUED 1241 AM CST Wed Dec 27 2023/ ...Synopsis... Cool temperatures and moist fuels across most of the CONUS will limit fire weather concerns on Thursday, as a closed upper low slowly drifts east across the Ohio Valley. ...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 1112 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered thunderstorms are forecast across the Florida Keys and far southern Florida early on Thursday. Severe storms appear unlikely. ...Synopsis and Discussion... A large, deep-layer cyclone will move east across the lower MS to OH Valleys, with a broad area of strong southwesterlies aloft across the Southeast. While high pressure will maintain stable conditions over much of the CONUS, an unstable warm sector will exist ahead of the cold front as it moves from the far southeast Gulf of Mexico toward the Bahamas. Ahead of an embedded shortwave trough within the southwest flow regime, a surface low is forecast to move across the FL Straits, south of a cold front which will continue to push south. It appears unlikely that the low will be strong enough to counteract the undercutting cool/stable air mass, but the boundary could stall briefly just offshore until the low passes. The most likely result is for elevated instability to be present atop the cooler air mass, supporting scattered thunderstorms with several hundred J/kg MUCAPE. Lift will be enhanced by the right-entrance region of the upper jet as well as warm advection around 850 mb. Wind profiles will favor supercells over the Straits, but the severe risk is expected to be mitigated over land due to the post-frontal air mass/decoupled boundary layer, rendering low-level shear ineffective. ..Jewell.. 12/27/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered thunderstorms are forecast across the Florida Keys and far southern Florida early on Thursday. Severe storms appear unlikely. ...Synopsis and Discussion... A large, deep-layer cyclone will move east across the lower MS to OH Valleys, with a broad area of strong southwesterlies aloft across the Southeast. While high pressure will maintain stable conditions over much of the CONUS, an unstable warm sector will exist ahead of the cold front as it moves from the far southeast Gulf of Mexico toward the Bahamas. Ahead of an embedded shortwave trough within the southwest flow regime, a surface low is forecast to move across the FL Straits, south of a cold front which will continue to push south. It appears unlikely that the low will be strong enough to counteract the undercutting cool/stable air mass, but the boundary could stall briefly just offshore until the low passes. The most likely result is for elevated instability to be present atop the cooler air mass, supporting scattered thunderstorms with several hundred J/kg MUCAPE. Lift will be enhanced by the right-entrance region of the upper jet as well as warm advection around 850 mb. Wind profiles will favor supercells over the Straits, but the severe risk is expected to be mitigated over land due to the post-frontal air mass/decoupled boundary layer, rendering low-level shear ineffective. ..Jewell.. 12/27/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered thunderstorms are forecast across the Florida Keys and far southern Florida early on Thursday. Severe storms appear unlikely. ...Synopsis and Discussion... A large, deep-layer cyclone will move east across the lower MS to OH Valleys, with a broad area of strong southwesterlies aloft across the Southeast. While high pressure will maintain stable conditions over much of the CONUS, an unstable warm sector will exist ahead of the cold front as it moves from the far southeast Gulf of Mexico toward the Bahamas. Ahead of an embedded shortwave trough within the southwest flow regime, a surface low is forecast to move across the FL Straits, south of a cold front which will continue to push south. It appears unlikely that the low will be strong enough to counteract the undercutting cool/stable air mass, but the boundary could stall briefly just offshore until the low passes. The most likely result is for elevated instability to be present atop the cooler air mass, supporting scattered thunderstorms with several hundred J/kg MUCAPE. Lift will be enhanced by the right-entrance region of the upper jet as well as warm advection around 850 mb. Wind profiles will favor supercells over the Straits, but the severe risk is expected to be mitigated over land due to the post-frontal air mass/decoupled boundary layer, rendering low-level shear ineffective. ..Jewell.. 12/27/2023 Read more