Aggregator

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1241 AM CST Wed Dec 27 2023 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A large upper cyclone, centered over the central CONUS will slowly drift east during the period today. East of the upper low, warm/moist conditions have spread up the East Coast. Meanwhile, high pressure has brought cool conditions to the Intermountain West. Cool and/or moist conditions across most of the CONUS, combined with moist fuels will preclude the fire-weather threat today. ..Bentley.. 12/27/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 states on Thursday. ...Synopsis... A large upper cyclone centered over the Mid-MS Valley, and attendant trough extending well south over the Gulf of Mexico will pivot slowly east on Thursday. A reinforcing shortwave trough rotating through the back side of this system will maintain general troughing over the CONUS east of the MS River into early Friday. At the surface, low pressure off the Mid-Atlantic coast will lift northeast offshore from the Northeast coast. An attendant cold front will push further offshore over the Atlantic while the southern extent of the front pushes deep into the Gulf of Mexico. Strong high pressure building over the Rockies and Plains, along with a dearth of boundary-layer moisture, will preclude thunderstorm potential east of the Rockies. Meanwhile, an amplified upper ridge will encompass the western half of the CONUS with most dry conditions expected beneath the influence of the ridge. ..Leitman.. 12/27/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 states on Thursday. ...Synopsis... A large upper cyclone centered over the Mid-MS Valley, and attendant trough extending well south over the Gulf of Mexico will pivot slowly east on Thursday. A reinforcing shortwave trough rotating through the back side of this system will maintain general troughing over the CONUS east of the MS River into early Friday. At the surface, low pressure off the Mid-Atlantic coast will lift northeast offshore from the Northeast coast. An attendant cold front will push further offshore over the Atlantic while the southern extent of the front pushes deep into the Gulf of Mexico. Strong high pressure building over the Rockies and Plains, along with a dearth of boundary-layer moisture, will preclude thunderstorm potential east of the Rockies. Meanwhile, an amplified upper ridge will encompass the western half of the CONUS with most dry conditions expected beneath the influence of the ridge. ..Leitman.. 12/27/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 states on Thursday. ...Synopsis... A large upper cyclone centered over the Mid-MS Valley, and attendant trough extending well south over the Gulf of Mexico will pivot slowly east on Thursday. A reinforcing shortwave trough rotating through the back side of this system will maintain general troughing over the CONUS east of the MS River into early Friday. At the surface, low pressure off the Mid-Atlantic coast will lift northeast offshore from the Northeast coast. An attendant cold front will push further offshore over the Atlantic while the southern extent of the front pushes deep into the Gulf of Mexico. Strong high pressure building over the Rockies and Plains, along with a dearth of boundary-layer moisture, will preclude thunderstorm potential east of the Rockies. Meanwhile, an amplified upper ridge will encompass the western half of the CONUS with most dry conditions expected beneath the influence of the ridge. ..Leitman.. 12/27/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Wed Dec 27 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 states on Thursday. ...Synopsis... A large upper cyclone centered over the Mid-MS Valley, and attendant trough extending well south over the Gulf of Mexico will pivot slowly east on Thursday. A reinforcing shortwave trough rotating through the back side of this system will maintain general troughing over the CONUS east of the MS River into early Friday. At the surface, low pressure off the Mid-Atlantic coast will lift northeast offshore from the Northeast coast. An attendant cold front will push further offshore over the Atlantic while the southern extent of the front pushes deep into the Gulf of Mexico. Strong high pressure building over the Rockies and Plains, along with a dearth of boundary-layer moisture, will preclude thunderstorm potential east of the Rockies. Meanwhile, an amplified upper ridge will encompass the western half of the CONUS with most dry conditions expected beneath the influence of the ridge. ..Leitman.. 12/27/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Synopsis... A large deep-layer cyclone centered over the mid MS Valley will slowly move east through tonight. An embedded mid-level disturbance will rotate through the outer orbit of the large-scale cyclone and move from the lower MS Valley to Long Island during the period. Weak buoyancy will primarily be relegated to the coastal areas of the Mid-Atlantic states, but it may develop as far inland in pockets across the central Appalachians during the day, as a surface low migrates north near the coast. As a result, scattered showers and a few weak thunderstorms are possible. The limited instability will likely preclude severe thunderstorm activity. Farther west, a potent mid-level trough/closed low west of the Pacific Northwest will feature an impulse moving into the coastal areas of northern CA and coastal OR/WA during the day. Cold 500-mb temperatures will probably yield 100-200 J/kg MUCAPE and a few lightning flashes with the deeper convection as it moves ashore. Elsewhere, tranquil conditions will prevail across a large part of the Interior West across the southern U.S. and influenced by surface high pressure. ..Smith/Bentley.. 12/27/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Synopsis... A large deep-layer cyclone centered over the mid MS Valley will slowly move east through tonight. An embedded mid-level disturbance will rotate through the outer orbit of the large-scale cyclone and move from the lower MS Valley to Long Island during the period. Weak buoyancy will primarily be relegated to the coastal areas of the Mid-Atlantic states, but it may develop as far inland in pockets across the central Appalachians during the day, as a surface low migrates north near the coast. As a result, scattered showers and a few weak thunderstorms are possible. The limited instability will likely preclude severe thunderstorm activity. Farther west, a potent mid-level trough/closed low west of the Pacific Northwest will feature an impulse moving into the coastal areas of northern CA and coastal OR/WA during the day. Cold 500-mb temperatures will probably yield 100-200 J/kg MUCAPE and a few lightning flashes with the deeper convection as it moves ashore. Elsewhere, tranquil conditions will prevail across a large part of the Interior West across the southern U.S. and influenced by surface high pressure. ..Smith/Bentley.. 12/27/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Synopsis... A large deep-layer cyclone centered over the mid MS Valley will slowly move east through tonight. An embedded mid-level disturbance will rotate through the outer orbit of the large-scale cyclone and move from the lower MS Valley to Long Island during the period. Weak buoyancy will primarily be relegated to the coastal areas of the Mid-Atlantic states, but it may develop as far inland in pockets across the central Appalachians during the day, as a surface low migrates north near the coast. As a result, scattered showers and a few weak thunderstorms are possible. The limited instability will likely preclude severe thunderstorm activity. Farther west, a potent mid-level trough/closed low west of the Pacific Northwest will feature an impulse moving into the coastal areas of northern CA and coastal OR/WA during the day. Cold 500-mb temperatures will probably yield 100-200 J/kg MUCAPE and a few lightning flashes with the deeper convection as it moves ashore. Elsewhere, tranquil conditions will prevail across a large part of the Interior West across the southern U.S. and influenced by surface high pressure. ..Smith/Bentley.. 12/27/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Tue Dec 26 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Synopsis... A large deep-layer cyclone centered over the mid MS Valley will slowly move east through tonight. An embedded mid-level disturbance will rotate through the outer orbit of the large-scale cyclone and move from the lower MS Valley to Long Island during the period. Weak buoyancy will primarily be relegated to the coastal areas of the Mid-Atlantic states, but it may develop as far inland in pockets across the central Appalachians during the day, as a surface low migrates north near the coast. As a result, scattered showers and a few weak thunderstorms are possible. The limited instability will likely preclude severe thunderstorm activity. Farther west, a potent mid-level trough/closed low west of the Pacific Northwest will feature an impulse moving into the coastal areas of northern CA and coastal OR/WA during the day. Cold 500-mb temperatures will probably yield 100-200 J/kg MUCAPE and a few lightning flashes with the deeper convection as it moves ashore. Elsewhere, tranquil conditions will prevail across a large part of the Interior West across the southern U.S. and influenced by surface high pressure. ..Smith/Bentley.. 12/27/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 PM CST Tue Dec 26 2023 Valid 270100Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms will not occur through tonight across the contiguous United States. ...Synopsis... Water-vapor imagery early this evening shows a large gyre centered over the lower MO Valley with weak mid-level ridges located along the East and West coasts. A moist/warm conveyor is located over the Carolinas northward into the upper OH Valley, where scant buoyancy was observed (i.e., Carolinas per 00z raob data) or forecast later tonight. This weak instability may lead to a few widely spaced, isolated lightning flashes tonight over the Carolinas, and perhaps as far north as the upper OH Valley. Elsewhere, cool and/or stable conditions will preclude thunderstorm development across the CONUS. ..Smith.. 12/27/2023 Read more

No Mesoscale Discussions are in effect as of Tue Dec 26 22:13:02 UTC 2023.

No watches are valid as of Tue Dec 26 22:13:02 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Tue Dec 26 2023 Valid 281200Z - 031200Z The potential for critical fire-weather conditions is low through the extended forecast period. On D4/Friday, a persistent midlevel low will gradually devolve into a positive-tilt trough over the eastern CONUS, while a related southwesterly jet streak overspreads the Southeast and Mid-Atlantic. A modest pressure gradient beneath the strong flow aloft will favor breezy/gusty surface winds across much of the Southeast into the southern Mid-Atlantic states, where marginal RH reductions are possible. However, generally cool surface temperatures and recent/ongoing rainfall should limit most fire-weather concerns here. Thereafter, an unconsolidated/split-flow pattern is expected across the CONUS, which will generally limit the development/overlap of warm/dry/windy conditions. One exception may be on D6/Sunday across the southern High Plains, where a southern-stream jet max may promote dry/breezy downslope flow. With that said, critical conditions are unlikely owing to marginal fuels. ..Weinman.. 12/26/2023 ...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 0154 PM CST Tue Dec 26 2023 Valid 281200Z - 031200Z The potential for critical fire-weather conditions is low through the extended forecast period. On D4/Friday, a persistent midlevel low will gradually devolve into a positive-tilt trough over the eastern CONUS, while a related southwesterly jet streak overspreads the Southeast and Mid-Atlantic. A modest pressure gradient beneath the strong flow aloft will favor breezy/gusty surface winds across much of the Southeast into the southern Mid-Atlantic states, where marginal RH reductions are possible. However, generally cool surface temperatures and recent/ongoing rainfall should limit most fire-weather concerns here. Thereafter, an unconsolidated/split-flow pattern is expected across the CONUS, which will generally limit the development/overlap of warm/dry/windy conditions. One exception may be on D6/Sunday across the southern High Plains, where a southern-stream jet max may promote dry/breezy downslope flow. With that said, critical conditions are unlikely owing to marginal fuels. ..Weinman.. 12/26/2023 ...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 0154 PM CST Tue Dec 26 2023 Valid 281200Z - 031200Z The potential for critical fire-weather conditions is low through the extended forecast period. On D4/Friday, a persistent midlevel low will gradually devolve into a positive-tilt trough over the eastern CONUS, while a related southwesterly jet streak overspreads the Southeast and Mid-Atlantic. A modest pressure gradient beneath the strong flow aloft will favor breezy/gusty surface winds across much of the Southeast into the southern Mid-Atlantic states, where marginal RH reductions are possible. However, generally cool surface temperatures and recent/ongoing rainfall should limit most fire-weather concerns here. Thereafter, an unconsolidated/split-flow pattern is expected across the CONUS, which will generally limit the development/overlap of warm/dry/windy conditions. One exception may be on D6/Sunday across the southern High Plains, where a southern-stream jet max may promote dry/breezy downslope flow. With that said, critical conditions are unlikely owing to marginal fuels. ..Weinman.. 12/26/2023 ...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 0154 PM CST Tue Dec 26 2023 Valid 281200Z - 031200Z The potential for critical fire-weather conditions is low through the extended forecast period. On D4/Friday, a persistent midlevel low will gradually devolve into a positive-tilt trough over the eastern CONUS, while a related southwesterly jet streak overspreads the Southeast and Mid-Atlantic. A modest pressure gradient beneath the strong flow aloft will favor breezy/gusty surface winds across much of the Southeast into the southern Mid-Atlantic states, where marginal RH reductions are possible. However, generally cool surface temperatures and recent/ongoing rainfall should limit most fire-weather concerns here. Thereafter, an unconsolidated/split-flow pattern is expected across the CONUS, which will generally limit the development/overlap of warm/dry/windy conditions. One exception may be on D6/Sunday across the southern High Plains, where a southern-stream jet max may promote dry/breezy downslope flow. With that said, critical conditions are unlikely owing to marginal fuels. ..Weinman.. 12/26/2023 ...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 0134 PM CST Tue Dec 26 2023 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. No changes are required to the existing outlook, with only general thunderstorms expected over parts of the Southeast. ..Jewell.. 12/26/2023 .PREV DISCUSSION... /ISSUED 1018 AM CST Tue Dec 26 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0134 PM CST Tue Dec 26 2023 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. No changes are required to the existing outlook, with only general thunderstorms expected over parts of the Southeast. ..Jewell.. 12/26/2023 .PREV DISCUSSION... /ISSUED 1018 AM CST Tue Dec 26 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0134 PM CST Tue Dec 26 2023 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. No changes are required to the existing outlook, with only general thunderstorms expected over parts of the Southeast. ..Jewell.. 12/26/2023 .PREV DISCUSSION... /ISSUED 1018 AM CST Tue Dec 26 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0134 PM CST Tue Dec 26 2023 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. No changes are required to the existing outlook, with only general thunderstorms expected over parts of the Southeast. ..Jewell.. 12/26/2023 .PREV DISCUSSION... /ISSUED 1018 AM CST Tue Dec 26 2023/ ...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. Read more