Aggregator

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 08 2024 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are possible from the Lower Mississippi Valley into much of the Southeast States on Monday. The probability for severe thunderstorms is low. ...Synopsis and Discussion... The upper pattern is forecast to undergo significant amplification on Monday, resulting in a deep upper trough that is expected to extend across much of the CONUS by Tuesday morning. The initial evolution of this upper trough will begin as a shortwave trough moves through the Great Basin into the Southwest while another moves from the Upper Midwest across the Upper Great Lakes and Ontario. A surface low attendant to the Upper Midwest/Upper Great Lakes shortwave trough will move eastward just ahead of its parent shortwave. As it does, an associated cold front will push southeastward through the Mid MS and the Lower OH Valleys, and the southern Plains. A secondary low is forecast to develop along the front across north TX, before then moving eastward and ending the period over northern LA/west-central MS. This overall evolution will encourage the development of a broad warm sector across the Lower MS Valley and Southeast, with dewpoints likely reaching the mid 60s before the front moves through. A broad area of precipitation is anticipated within this warm sector throughout the day, but buoyancy will be minimized by poor lapse rates and relatively warm profiles. Initially strong low-level flow will weaken throughout the day before then increasing again Monday night ahead of the front. This will lengthen low-level hodographs, with low-level shear high enough to support severe potential. Localized severe potential may exist near the surface low as it moves across the ArkLaMiss vicinity late Monday night. However, minimal buoyancy will remain in place, with surface stability potentially persisting as well. These factors suggest the overall severe threat will remain low, precluding the need for any probabilities. ..Mosier.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sat Dec 07 2024 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Rain/rain showers, and possibly occasional lightning in some areas, will spread across the Lower Mississippi and Tennessee Valleys today. Severe weather is not expected. ...Discussion... An upper low in the southern branch of a split-flow regime across the U.S. will shift eastward across the southern Plains through the day, before devolving into an open wave and accelerating across the Mid and Lower Mississippi Valley and into the Lower Ohio and Tennessee Valley areas overnight. Ahead of the advancing low/trough, a broad zone of warm advection/quasigeostropic ascent will support widespread precipitation, including elevated convection. Occasional lightning may accompany the convection locally, but due to weak CAPE, and the elevated nature of the convection, severe weather is not expected. ..Goss/Moore.. 12/08/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0625 PM CST Sat Dec 07 2024 Valid 080100Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...01z Update... Southern-stream short-wave trough is advancing across NM/northern Mexico as 500mb speed max translates into the Big Bend region. Downstream, LLJ is focused across east TX and this should gradually shift east overnight. Radar data supports this with significant precip shield from southeast OK into northeast TX. While most of this convection has been, and will likely continue to be, lightning-free, a few elevated thunderstorms may yet develop across this region ahead of the approaching short wave. Scattered, weak convection is expected to develop across the Pacific Northwest ahead of a short-wave trough tonight. Greatest potential for lightning will be with updrafts influenced by the marine layer, where buoyancy is bit higher. ..Darrow.. 12/08/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0625 PM CST Sat Dec 07 2024 Valid 080100Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected tonight. ...01z Update... Southern-stream short-wave trough is advancing across NM/northern Mexico as 500mb speed max translates into the Big Bend region. Downstream, LLJ is focused across east TX and this should gradually shift east overnight. Radar data supports this with significant precip shield from southeast OK into northeast TX. While most of this convection has been, and will likely continue to be, lightning-free, a few elevated thunderstorms may yet develop across this region ahead of the approaching short wave. Scattered, weak convection is expected to develop across the Pacific Northwest ahead of a short-wave trough tonight. Greatest potential for lightning will be with updrafts influenced by the marine layer, where buoyancy is bit higher. ..Darrow.. 12/08/2024 Read more

No Mesoscale Discussions are in effect as of Sat Dec 7 21:50:02 UTC 2024.

No watches are valid as of Sat Dec 7 21:50:02 UTC 2024.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0318 PM CST Sat Dec 07 2024 Valid 091200Z - 151200Z ...Days 3-5/Monday-Wednesday - Southern California... Large-scale trough amplification is forecast over the western CONUS early next week. At the same time, an upstream ridge over the eastern Pacific strengthen. This pattern will result in strengthening surface high pressure over the Intermountain West. Offshore pressure gradients will tighten across southern CA (LAX-DAG gradient peaking around -7 to -8.5 mb). This pattern will favor critical fire-weather conditions across portions of Ventura and Los Angeles Counties in southern CA, given increasingly dry/receptive fuels. Confidence in the development of critical conditions is highest on Day 4/Tuesday as the pressure gradient peaks, and 70-percent Critical probabilities have been maintained with this outlook. The 40 percent region was expanded further southward to account for trends in recent data suggesting more widespread Elevated to Critical conditions. Areas of Extremely Critical conditions may be possible Tuesday where single digits humidities overlap stronger winds in favored downslope regions of the mountains and foothills. Fire weather concerns may linger into Wednesday morning before gradients begin to gradually weaken through the day. Given the potential for a long period of Critical conditions prior, a 40 percent delineation was added to cover the continuance of this threat overnight Tuesday into the late morning Wednesday. As the western trough ejects across the Plains D4/Tuesday into D5/Wednesday, periods of dry/windy conditions are expected across the High/Southern Plains, however, fuels do not appear supportive of large-fire potential at this time. Additional precipitation will be possible across portions of the Southern Plains which may also contribute to less receptive fuels. ..Thornton.. 12/07/2024 ...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 0147 PM CST Sat Dec 07 2024 Valid 072000Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20z Update... No changes. Weak mid-level warm advection will continue to support isolated thunderstorms through this afternoon across parts of central and eastern TX. Recent Hi-res guidance also suggests storms will gradually decrease in coverage with lightning becoming more sporadic through tonight. Isolated thunderstorms are possible over parts of the Pacific Northwest with weak buoyancy and steepening mid-level lapse rates ahead of the advancing Pacific Trough. Severe storms are not expected, see the prior discussion. ..Lyons.. 12/07/2024 .PREV DISCUSSION... /ISSUED 1029 AM CST Sat Dec 07 2024/ ...TX... Broad southwest flow aloft will maintain mid-level warm/moist advection and persistent showers and isolated thunderstorms through the forecast period. It appears the highest probability of lightning will be this afternoon, with decreasing coverage after dark. No severe storms are expected. ...Northwest WA... A few thunderstorms are possible this evening and tonight over northwest WA as a progressive upper trough and associated cold pocket aloft moves into the area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0147 PM CST Sat Dec 07 2024 Valid 072000Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20z Update... No changes. Weak mid-level warm advection will continue to support isolated thunderstorms through this afternoon across parts of central and eastern TX. Recent Hi-res guidance also suggests storms will gradually decrease in coverage with lightning becoming more sporadic through tonight. Isolated thunderstorms are possible over parts of the Pacific Northwest with weak buoyancy and steepening mid-level lapse rates ahead of the advancing Pacific Trough. Severe storms are not expected, see the prior discussion. ..Lyons.. 12/07/2024 .PREV DISCUSSION... /ISSUED 1029 AM CST Sat Dec 07 2024/ ...TX... Broad southwest flow aloft will maintain mid-level warm/moist advection and persistent showers and isolated thunderstorms through the forecast period. It appears the highest probability of lightning will be this afternoon, with decreasing coverage after dark. No severe storms are expected. ...Northwest WA... A few thunderstorms are possible this evening and tonight over northwest WA as a progressive upper trough and associated cold pocket aloft moves into the area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0147 PM CST Sat Dec 07 2024 Valid 072000Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20z Update... No changes. Weak mid-level warm advection will continue to support isolated thunderstorms through this afternoon across parts of central and eastern TX. Recent Hi-res guidance also suggests storms will gradually decrease in coverage with lightning becoming more sporadic through tonight. Isolated thunderstorms are possible over parts of the Pacific Northwest with weak buoyancy and steepening mid-level lapse rates ahead of the advancing Pacific Trough. Severe storms are not expected, see the prior discussion. ..Lyons.. 12/07/2024 .PREV DISCUSSION... /ISSUED 1029 AM CST Sat Dec 07 2024/ ...TX... Broad southwest flow aloft will maintain mid-level warm/moist advection and persistent showers and isolated thunderstorms through the forecast period. It appears the highest probability of lightning will be this afternoon, with decreasing coverage after dark. No severe storms are expected. ...Northwest WA... A few thunderstorms are possible this evening and tonight over northwest WA as a progressive upper trough and associated cold pocket aloft moves into the area. Read more