Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Fri Dec 27 2024 Valid 281200Z - 291200Z Guidance has trended southwestward with a northwesterly 850 mb jet across part of the south-central CONUS tomorrow afternoon. This has led to a trend for increasing wind speeds across parts of the Texas Hill Country near the Rio Grande. Latest guidance suggests the potential for gusts to 25-35 mph during the afternoon. In addition, fuels in this region are modestly dry, with 10-hour fuel moisture values near the 5th percentile. Given the upward trend in wind speeds, have elected to introduce a small Elevated area. Otherwise, the forecast remains on track. See the previous discussion for further details. ..Supinie.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1233 AM CST Fri Dec 27 2024/ ...Synopsis... A mid-level trough will exit the Plains on D2/Saturday before moving across the southeastern US. High pressure will build in across the western US, with heights rising over the Rockies. Cooler northwesterly flow will filter across the high terrain and into the Plains, with increasing relative humidity. Some strong northwesterly breezes will overlap relative-humidity reductions to around 15 percent across portions of far western Texas. Latest fuels guidance indicates that fuels within this region will not support wildfire spread, precluding need to include areas at this time. ...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 0153 PM CST Fri Dec 27 2024 Valid 281200Z - 291200Z Guidance has trended southwestward with a northwesterly 850 mb jet across part of the south-central CONUS tomorrow afternoon. This has led to a trend for increasing wind speeds across parts of the Texas Hill Country near the Rio Grande. Latest guidance suggests the potential for gusts to 25-35 mph during the afternoon. In addition, fuels in this region are modestly dry, with 10-hour fuel moisture values near the 5th percentile. Given the upward trend in wind speeds, have elected to introduce a small Elevated area. Otherwise, the forecast remains on track. See the previous discussion for further details. ..Supinie.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1233 AM CST Fri Dec 27 2024/ ...Synopsis... A mid-level trough will exit the Plains on D2/Saturday before moving across the southeastern US. High pressure will build in across the western US, with heights rising over the Rockies. Cooler northwesterly flow will filter across the high terrain and into the Plains, with increasing relative humidity. Some strong northwesterly breezes will overlap relative-humidity reductions to around 15 percent across portions of far western Texas. Latest fuels guidance indicates that fuels within this region will not support wildfire spread, precluding need to include areas at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2291 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF FAR EASTERN MISSISSIPPI INTO WESTERN ALABAMA
Mesoscale Discussion 2291 NWS Storm Prediction Center Norman OK 1232 PM CST Fri Dec 27 2024 Areas affected...portions of far eastern Mississippi into western Alabama Concerning...Severe potential...Watch unlikely Valid 271832Z - 272100Z Probability of Watch Issuance...20 percent SUMMARY...An isolated threat for damaging gusts and tornadoes will persist into the afternoon hours. A WW issuance is not expected. DISCUSSION...A band of thunderstorms persist along the MS/AL border, near the Gulf Coast, and these storms have shown some brief bouts of low-level rotation over the past several hours. Regional VADs across eastern MS into AL show gradually shrinking hodographs as the low-level jet continues to drift northeast, away from the warm sector. However, a robust mid-level trough is beginning to overspread the southern MS Valley, which may help preserve a favorable deep-layer shear field along the Gulf Coast during the afternoon. Continued surface heating may support MLCAPE approaching the 750-1000 J/kg range given mid 60s F dewpoints near the coast. Overall, storms should continue to oscillate in intensity through mid afternoon, with continued instances of low-level rotation possible. Isolated damaging gusts and tornadoes remain the main threats. The most immediate threat exists with storms approaching the Mobile Bay area. However, convection has attempted to intensify over far east-central MS with the approach of the mid-level trough. Confidence in these storms reaching severe limits is overall lower, but a stray damaging gust or tornado cannot be ruled out with any storms that intensify in this regime. Either way, the isolated nature of the severe threat suggests that a WW issuance is not anticipated. ..Squitieri/Hart.. 12/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BMX...MOB...JAN...LIX... LAT...LON 30218984 31398957 32048931 32698896 33048871 33408835 33248802 32728788 32038767 31408739 30898727 30548728 30278757 30118862 30218984 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Fri Dec 27 2024 Valid 272000Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM SOUTHEAST LA/MS INTO SOUTHWEST AL AND THE WESTERN FL PANHANDLE... ...SUMMARY... A few strong to locally severe thunderstorms could occur today across parts of the central Gulf Coast States. ...20Z Update... Only minor adjustments to the Marginal and general thunderstorm areas based on current observation/activity in parts of southern Louisiana. Additional convection is developing in the wake of this morning's activity in eastern/southern Mississippi. With the modest destabilization that has occurred this afternoon, these storms will be capable of a marginal wind/tornado threat. Further details available in the previous discussion below. ..Wendt.. 12/27/2024 .PREV DISCUSSION... /ISSUED 1024 AM CST Fri Dec 27 2024/ ...Central Gulf Coast Region... A compact negative-tilted shortwave trough that has provided occasionally strong thunderstorms to parts of southern MS/southeast LA is tracking away from the Gulf Coast region. Low-level winds are slowly veering/decreasing with time, suggesting the threat of supercell structures and associated severe threat is marginal through mid-afternoon. Another strong upper trough that is now over north TX will graze the same area late this afternoon, possibly resulting in a re-invigoration of convection across southeast MS and southwest AL. The air mass has been slow to recover, with mid 60s dewpoints restricted to areas just a few rows of counties inland. Widespread clouds will also limit destabilization. Locally gusty winds or a brief tornado will remain possible with this renewed early evening activity, but the overall threat appears marginal. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Fri Dec 27 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND THE CAROLINAS... ...SUMMARY... Severe storms are possible across parts of the Southeast States on Sunday. ...Synopsis... An upper trough over the MS Valley is forecast to continue to amplify as moves into the southeastern/eastern US Sunday. Strong mid-level flow ahead of the trough and a deepening surface low will overspread a moistening air mass from the Carolinas to the Atlantic Coast. Weak to moderate buoyancy and strong deep and low-level shear will support a risk for strong to severe storms capable of damaging gusts and a couple of tornadoes. ...Southeast... One or more broken bands of storms are expected to be ongoing early Sunday morning across parts of AL or western GA ahead of the cold front trailing the surface low through the OH Valley. As the upper trough progresses eastward, gradual reintensification of this convection is expected through the early afternoon as moderate height falls overspread lower to middle 60s F surface dewpoints into parts of the Southeast and the Carolinas. Additional storms are possible ahead of the primary band with some diurnal heating. However, lingering cloud cover and the rapid low-level temperature advection ahead of the low is expected to keep cloud cover relatively dense, limiting buoyancy (max of 500-1000 J/kg of MLCAPE). This is especially so with northward extent where quite limited instability is likely into southern VA and the Mid Atlantic at the nose of the low-level moisture plume. Still, relatively moist surface conditions will allow for robust convection across the risk area with a mix of line segments and a few semi-discrete supercells given favorable deep-layer shear of 40-60 kt. The strong mid and low-level flow will support a risk of damaging gusts and perhaps a couple of tornadoes with the stronger storms into the evening, before weakening buoyancy reduces the overall severe risk. ... Upper OH Valley... Beneath the primary mid-level cold core near the center of the surface low, differential temperature advection atop low 50s F dewpoints may steepen low/mid-level lapse rates sufficiently for marginal diurnal destabilization of a few hundred J/kg of MUCAPE. This may support a risk for a few damaging wind gusts or small hail with low-topped strong storms given 45-60 kt of low-level flow beneath the upper trough. ..Lyons.. 12/27/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Fri Dec 27 2024 Valid 281200Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF EAST TEXAS...THE LOWER MISSISSIPPI RIVER VALLEY INTO THE TENNESSEE VALLEY... ...SUMMARY... A regional outbreak of severe storms, with large hail, damaging winds, and strong tornadoes is possible Saturday into Saturday night, from East Texas, across the Lower Mississippi Valley, into parts of the Tennessee Valley. ...Synopsis... Mid-level flow is expected to rapidly amplify over the southern CONUS Saturday, as several southern stream perturbations intensify as they move near the Gulf Coast. A prominent shortwave trough, initial located across the southern OH Valley, will quickly eject northward as a second stronger shortwave approaches from the southern Plains vicinity. A roughly east-west oriented warm front will quickly move inland overnight Friday and into early Saturday in response to increased mid-level height falls and a deepening surface low near the Red River. This will allow for robust moisture return, with upper 60s to low 70s F dewpoints likely across the lower MS Valley by daybreak. While clouds and precipitation from inland moisture advection may complicate destabilization to some degree, sufficient buoyancy is expected to support numerous strong to severe storms with all hazards possible from East TX and the lower MS valley, into the TN valley from Saturday morning into early Sunday. ...East TX, Lower MS Valley... As the mid-level flow pattern quickly amplifies Saturday, the prominent shortwave trough and a subtle lead wave over the southern plains should rapidly strengthen, taking on neutral to slightly negative tilts by 00z Sunday. As this occurs, increasingly strong diffluent flow aloft will overspread East Texas toward the ArkLaMiss vicinity, where middle 60s F surface dewpoints will become more common. Steepening low/mid-level lapse rates and diurnal heating should allow for moderate destabilization, despite some lingering clouds and isolated elevated storms. Deeper convection is expected to develop early in the period (11-14z) as ascent from the embedded perturbation and main trough move over a pre-frontal confluence axis across East TX/Western LA. A second round of robust convection may also develop across eastern TX later in the afternoon as a Pacific front associated with the surface low over North TX impinges on the warm sector from the west. A mix of semi-discrete supercells and linearly organized bowing segments are expected with sufficient buoyancy/deep-layer shear overlap for storm organization. An initial risk for large hail, especially where low-level flow is somewhat veered, should transition to a risk for damaging winds and tornadoes as 0-1 km SRH increases to 150-300 m2/s2 into mid/late Saturday afternoon with a 35+ kt 850 mb low-level jet. Convection should quickly spread northeast into the lower MS Valley, peaking in intensity through the afternoon and early evening hours. Coincident with an increase in the low-level jet to 45-65 kt and intensifying surface pressure falls, low-level hodographs will expand with 0-1 km SRH of 300-400 m2/s2 likely. This will support the potential for strong tornadoes with any established suppercellular elements. ...Tennessee Valley and Cumberland Plateau... As the upper trough continues to amplify through the day, the warm front will gradually lift north into the southern TN valley by early afternoon. A broad area of cloud cover and perhaps light stratiform precipitation is expected in the presence of strong isentropic ascent along the advancing warm front. This remains the primary uncertainty regarding the northern/eastern extent of the surface-based severe risk later Saturday afternoon into Saturday night. While buoyancy/destabilization may be muted, the intensifying upper trough and surface low will favor very strong low and mid-level wind fields supportive of storm organization into Saturday evening and early Sunday. With very large low-level hodographs (0-1 km SRH 300-500 m2/s2) weakly buoyant near-surface based parcels will still allow for some tornado and or damaging wind risk into the overnight hours, especially with any established supercell or bowing structures across parts of AL, TN and western GA. ..Lyons.. 12/27/2024 Read more