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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1135 AM CST Sat Dec 09 2023 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE SOUTHEAST AND TOWARD PARTS OF THE MID ATLANTIC... ...SUMMARY... Isolated severe thunderstorms will be possible through Sunday evening across parts of the Southeast States, mainly in the form of sporadic damaging winds and a few brief tornadoes. ...Synopsis... A highly amplified upper trough will move from the MS Valley toward the East Coast on Sunday, with a primary embedded speed max ejecting quickly from the northern Gulf Coast toward the Mid Atlantic. At the surface, a cold front will push east across the Appalachians during the afternoon, with the strongest frontal surge across the Southeast late in the day and into the evening. Ahead of the cold front, a surface trough will gradually deepen from MD southwestward to the FL Panhandle, with 40-50 kt southerly 850 mb flow aiding moistening. Front-parallel winds aloft as well as modest destabilization will likely lead to scattered storms, with a few becoming severe across the region. ...Parts of the Southeast and East Coast... Scattered storms are likely to be ongoing along the front from southern AL and the western FL Panhandle across northern GA and the Appalachians Sunday morning, with substantial low clouds across much of the region. Lack of appreciable heating will generally reduce available instability, but sufficient boundary layer moisture with low to perhaps mid 60s F dewpoints will result in a few hundred J/kg MLCAPE ahead of the cold front. The strongest cooling aloft will occur behind the boundary, as the upper trough will be quite amplified with meridional flow aloft. Storms across the Southeast may eventually become linear as the cold front accelerates, and this may yield a few damaging gusts. Low-level shear may also favor isolated supercells with brief tornado threat, with the main mitigating factor being lack of heating. Any pockets of strong heating that do develop could yield mesocale areas of higher potential, and the southeastern area will be monitored going into the Day 1 period. Farther north into the Mid Atlantic, boundary layer stability will likely reduce severe potential to Marginal Risk levels due to the combination of weak lift/convergence combined with the cloudy/saturated profiles. Still, strengthening mean winds in the lowest few km may support strong to perhaps damaging gusts. ..Jewell.. 12/09/2023 Read more

WW 0714 Status Updates
STATUS FOR WATCH 0714 HAS NOT BEEN ISSUED YET Read more

WW 0714 Status Updates
STATUS FOR WATCH 0714 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Sat Dec 9 16:52:02 UTC 2023.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...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 1041 AM CST Sat Dec 09 2023 Valid 091700Z - 101200Z The previous forecast remains on track with no changes required. Latest surface observations within the southern CA coastal ranges show areas of elevated to critical fire weather conditions with winds gusting between 25-50 mph and RH in the upper teens and low 20s. Such conditions will likely persist through tonight and into early Sunday morning. Across southern TX, dry conditions are noted in recent observations with a gradual increase in winds still likely this afternoon. See the previous discussion below for additional information. ..Moore.. 12/09/2023 .PREV DISCUSSION... /ISSUED 1141 PM CST Fri Dec 08 2023/ ...Synopsis... An upper-level trough will amplify as it moves into the Southeast today. This will push a cold front through the Plains to near the Appalachians. Surface high pressure will increase within the Great Basin and Four Corners regions. ...Southern California... Offshore winds will likely be maximized early this morning. Winds of 20-25 mph (with higher gusts) will overlap with at least marginally reduced RH. RH values will fall to near 10-15% in some locations by the afternoon. Winds will slowly lose some intensity with time, but should remain 15-20 mph for several hours. Lower elevation fuels will be the primary driver of fire spread. However, these fine fuels are only marginally dry at present. Elevated fire weather concerns are possible where these fuels are driest. ...Texas... Elevated fire weather is possible within part of the Permian Basin into the Edwards Plateau. Post-frontal winds will be 15-20 mph amid 15-20% RH. Locally lower RH could occur where a greater downsloping wind component exists. Fine fuels are marginally dry and will support a low-end threat for a large fire. Cold advection will tend to limit the fire weather threat, particularly farther north, as RH will likely remain above critical thresholds in those areas. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1036 AM CST Sat Dec 09 2023 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...GULF COAST...TENNESSEE VALLEY... ...SUMMARY... A few tornadoes, damaging thunderstorm wind gusts, and isolated severe hail are possible today and tonight from portions of the Ohio Valley southward to the Lower Mississippi Valley and middle Gulf Coast. ...Gulf Coast/Lower Mississippi Valley/Tennessee Valley... Region is being increasingly influenced by height falls but otherwise resides between larger scale influences of an upper trough over the Upper Midwest and a positive-tilt trough over the southern High Plains. Increasing warm-sector moisture (generally lower to some middle 60s F surface dewpoints) ahead of a southeastward-moving cold front, along with considerable deep-layer/low-level shear, will be favorable factors for a long-duration severe risk through the afternoon into tonight. However, the likelihood of a complex/mixed quasi-linear convective mode casts uncertainty regarding the magnitude of the severe risk, particularly regarding a supercell-related sustained/focused tornado risk. It is also noted that some guidance suggests that 1-3km AGL winds may somewhat weaken by late afternoon/early evening within the warm sector, while noting SRH will still remain favorable for rotating/severe storms. Storms should continue to increase in coverage through early afternoon, initially near the front across Arkansas northeastward into western portions of Tennessee/Kentucky. Sufficiently steep mid-level lapse rates will support some hail potential, especially the first part of the day, but the tendency for storm clustering will otherwise limit this overall potential, as well as limiting prospects for more consequential hail magnitudes. As the boundary layer warms this afternoon, the potential for initially semi-discrete supercells will increase along with related damaging wind risk as well as tornado potential, which will persist through the afternoon/evening even with a quasi-linear convective mode. As warm-sector inhibition further weakens later this afternoon, additional deepening convection may develop within weak pre-frontal convergence/confluence regime, mainly across Mississippi into Alabama, with this development eventually merging with or taking over as the main convective band this evening. Similarly, pre-frontal confluence may support isolated supercellular development along the Gulf Coast/Florida Panhandle vicinity through late night hours/early Sunday, within a somewhat separate regime capable of a few severe storms. ..Guyer/Weinman.. 12/09/2023 Read more