Severe Storms

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 29 2024 Valid 301200Z - 311200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm chances appear low on Monday. ...Synopsis... A departing upper-level trough will lift northeast early Monday as a surface cold front moves offshore over New England. An upstream upper-level trough will amplify as it moves into the central Plains, contributing to the development of a surface low near the KS/MO border by afternoon. Low-level moisture will begin to return north across the lower Mississippi Valley/Ark-La-Miss region, however richer moisture will remain confined to near the TX/LA coast. This will limit destabilization potential even as ascent/cooling mid-level temperatures develop near the surface low. Thus, while an isolated lightning strike will be possible in the presence of meager MUCAPE (around 100-200 J/kg) across the mid-Mississippi Valley area Monday night, overall coverage should be less than 10%. Elsewhere across the CONUS, generally dry/stable conditions should preclude thunderstorm potential. ..Bunting.. 12/29/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 29 2024 Valid 301200Z - 311200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm chances appear low on Monday. ...Synopsis... A departing upper-level trough will lift northeast early Monday as a surface cold front moves offshore over New England. An upstream upper-level trough will amplify as it moves into the central Plains, contributing to the development of a surface low near the KS/MO border by afternoon. Low-level moisture will begin to return north across the lower Mississippi Valley/Ark-La-Miss region, however richer moisture will remain confined to near the TX/LA coast. This will limit destabilization potential even as ascent/cooling mid-level temperatures develop near the surface low. Thus, while an isolated lightning strike will be possible in the presence of meager MUCAPE (around 100-200 J/kg) across the mid-Mississippi Valley area Monday night, overall coverage should be less than 10%. Elsewhere across the CONUS, generally dry/stable conditions should preclude thunderstorm potential. ..Bunting.. 12/29/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 29 2024 Valid 301200Z - 311200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm chances appear low on Monday. ...Synopsis... A departing upper-level trough will lift northeast early Monday as a surface cold front moves offshore over New England. An upstream upper-level trough will amplify as it moves into the central Plains, contributing to the development of a surface low near the KS/MO border by afternoon. Low-level moisture will begin to return north across the lower Mississippi Valley/Ark-La-Miss region, however richer moisture will remain confined to near the TX/LA coast. This will limit destabilization potential even as ascent/cooling mid-level temperatures develop near the surface low. Thus, while an isolated lightning strike will be possible in the presence of meager MUCAPE (around 100-200 J/kg) across the mid-Mississippi Valley area Monday night, overall coverage should be less than 10%. Elsewhere across the CONUS, generally dry/stable conditions should preclude thunderstorm potential. ..Bunting.. 12/29/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 29 2024 Valid 301200Z - 311200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm chances appear low on Monday. ...Synopsis... A departing upper-level trough will lift northeast early Monday as a surface cold front moves offshore over New England. An upstream upper-level trough will amplify as it moves into the central Plains, contributing to the development of a surface low near the KS/MO border by afternoon. Low-level moisture will begin to return north across the lower Mississippi Valley/Ark-La-Miss region, however richer moisture will remain confined to near the TX/LA coast. This will limit destabilization potential even as ascent/cooling mid-level temperatures develop near the surface low. Thus, while an isolated lightning strike will be possible in the presence of meager MUCAPE (around 100-200 J/kg) across the mid-Mississippi Valley area Monday night, overall coverage should be less than 10%. Elsewhere across the CONUS, generally dry/stable conditions should preclude thunderstorm potential. ..Bunting.. 12/29/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CST Sun Dec 29 2024 Valid 301200Z - 311200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm chances appear low on Monday. ...Synopsis... A departing upper-level trough will lift northeast early Monday as a surface cold front moves offshore over New England. An upstream upper-level trough will amplify as it moves into the central Plains, contributing to the development of a surface low near the KS/MO border by afternoon. Low-level moisture will begin to return north across the lower Mississippi Valley/Ark-La-Miss region, however richer moisture will remain confined to near the TX/LA coast. This will limit destabilization potential even as ascent/cooling mid-level temperatures develop near the surface low. Thus, while an isolated lightning strike will be possible in the presence of meager MUCAPE (around 100-200 J/kg) across the mid-Mississippi Valley area Monday night, overall coverage should be less than 10%. Elsewhere across the CONUS, generally dry/stable conditions should preclude thunderstorm potential. ..Bunting.. 12/29/2024 Read more

WW 0723 Status Updates
STATUS FOR WATCH 0723 HAS NOT BEEN ISSUED YET Read more

WW 0723 Status Updates
STATUS FOR WATCH 0723 HAS NOT BEEN ISSUED YET Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 0722 Status Updates
STATUS REPORT ON WW 722 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE SEM TO 25 SSE BHM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...BMX...HUN...MEG... STATUS REPORT FOR WT 722 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC001-005-011-015-017-019-027-029-037-049-051-055-071-081-085- 087-095-101-109-111-113-115-121-123-290740- AL . ALABAMA COUNTIES INCLUDED ARE AUTAUGA BARBOUR BULLOCK CALHOUN CHAMBERS CHEROKEE CLAY CLEBURNE COOSA DEKALB ELMORE ETOWAH JACKSON LEE LOWNDES MACON MARSHALL MONTGOMERY PIKE RANDOLPH RUSSELL ST. CLAIR TALLADEGA TALLAPOOSA TNC051-290740- TN . TENNESSEE COUNTIES INCLUDED ARE FRANKLIN Read more

WW 722 TORNADO AL MS 290210Z - 291000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 722 NWS Storm Prediction Center Norman OK 810 PM CST Sat Dec 28 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northern and Central Alabama Northeast Mississippi * Effective this Saturday night and Sunday morning from 810 PM until 400 AM CST. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Scattered damaging winds likely with isolated significant gusts to 75 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...A line of thunderstorms should continue to pose some threat for a few tornadoes and scattered to numerous damaging winds as it moves east-northeastward this evening and overnight. Any sustained supercell ahead of the line could produce a strong tornado, although severe/damaging winds should eventually tend to become the main threat overnight. The tornado watch area is approximately along and 50 statute miles east and west of a line from 20 miles north northeast of Muscle Shoals AL to 30 miles southwest of Selma AL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU2). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 720...WW 721... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26040. ...Gleason Read more

WW 0721 Status Updates
STATUS REPORT ON WW 721 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 W BVE TO 15 E MOB TO 30 SSE SEM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2312. ..GRAMS..12/29/24 ATTN...WFO...MOB...LIX... STATUS REPORT FOR WT 721 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC003-013-035-039-041-053-290740- AL . ALABAMA COUNTIES INCLUDED ARE BALDWIN BUTLER CONECUH COVINGTON CRENSHAW ESCAMBIA FLC033-091-113-290740- FL . FLORIDA COUNTIES INCLUDED ARE ESCAMBIA OKALOOSA SANTA ROSA LAC075-290740- LA . LOUISIANA PARISHES INCLUDED ARE PLAQUEMINES Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CST Sat Dec 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE EASTERN GULF COAST STATES AND CAROLINAS INTO FAR SOUTHERN VIRGINIA...... ...SUMMARY... Severe thunderstorms, associated with a threat for tornadoes, wind damage and hail, will be possible today from the eastern Gulf Coast northward into the Carolinas. More isolated severe storms may occur across parts of the central Appalachians and Ohio Valley. ...Southern Atlantic Coastal States... A large-scale mid-level trough will move northeastward through the Tennessee Valley and central Gulf Coast states today, as a cold front advances eastward into the southern Appalachian Mountains and eastern Gulf Coast states. At the start of the period, a line of strong thunderstorms will be ongoing from northwestern Georgia into southeast Alabama. This line could have an isolated wind-damage potential. This morning, surface temperatures will warm ahead of the line allowing for weak destabilization across much of eastern Georgia and the Carolinas. The right entrance region of the mid-level jet, associated with strong large-scale ascent, will pass over this area in conjunction with a 50 to 60 knot low-level jet. RAP forecast soundings near the jet axis have steep low-level lapse rates and 40 to 50 knots of flow just above the ground. For this reason, the more organized parts of the line should be able to easily mix the stronger winds to the surface, and result in severe wind gusts with the more intense parts of the line. Forecast soundings near the jet axis also have 0-3 km storm-relative helicity around 400 m2/s2. This will support an isolated tornado threat as well. Tornadoes will be most likely with rotating storms that develop within the line in areas that destabilize the most. The threat is expected to continue into the early to mid afternoon as the line moves into central North Carolina and eastern South Carolina. ...Central Appalachians/Ohio Valley... A mid-level large-scale trough and an associated surface low will move northeastward into the Ohio Valley today. An 80 to 90 knot mid-level jet will accompany the trough, spreading strong large-scale ascent across the region. Immediately ahead of the system, some surface heating will take place today across the Virginias and Ohio, where an axis of weak instability is expected to develop. RAP forecast soundings by early afternoon near the instability axis increase MLCAPE to around 400 J/kg. This should enable low-topped thunderstorms to develop ahead of the trough. Steep low-level lapse rates combined with 40 to 50 knots of flow just above the ground could be enough for marginally severe gusts. In addition, 0-3 km storm-relative helicity is expected to be near 300 m2/s2 which could also support a marginal tornado threat. The isolated severe threat is expected to be concentrated in the late morning and early afternoon as the mid-level jet moves across the region. ..Broyles/Thornton.. 12/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CST Sat Dec 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE EASTERN GULF COAST STATES AND CAROLINAS INTO FAR SOUTHERN VIRGINIA...... ...SUMMARY... Severe thunderstorms, associated with a threat for tornadoes, wind damage and hail, will be possible today from the eastern Gulf Coast northward into the Carolinas. More isolated severe storms may occur across parts of the central Appalachians and Ohio Valley. ...Southern Atlantic Coastal States... A large-scale mid-level trough will move northeastward through the Tennessee Valley and central Gulf Coast states today, as a cold front advances eastward into the southern Appalachian Mountains and eastern Gulf Coast states. At the start of the period, a line of strong thunderstorms will be ongoing from northwestern Georgia into southeast Alabama. This line could have an isolated wind-damage potential. This morning, surface temperatures will warm ahead of the line allowing for weak destabilization across much of eastern Georgia and the Carolinas. The right entrance region of the mid-level jet, associated with strong large-scale ascent, will pass over this area in conjunction with a 50 to 60 knot low-level jet. RAP forecast soundings near the jet axis have steep low-level lapse rates and 40 to 50 knots of flow just above the ground. For this reason, the more organized parts of the line should be able to easily mix the stronger winds to the surface, and result in severe wind gusts with the more intense parts of the line. Forecast soundings near the jet axis also have 0-3 km storm-relative helicity around 400 m2/s2. This will support an isolated tornado threat as well. Tornadoes will be most likely with rotating storms that develop within the line in areas that destabilize the most. The threat is expected to continue into the early to mid afternoon as the line moves into central North Carolina and eastern South Carolina. ...Central Appalachians/Ohio Valley... A mid-level large-scale trough and an associated surface low will move northeastward into the Ohio Valley today. An 80 to 90 knot mid-level jet will accompany the trough, spreading strong large-scale ascent across the region. Immediately ahead of the system, some surface heating will take place today across the Virginias and Ohio, where an axis of weak instability is expected to develop. RAP forecast soundings by early afternoon near the instability axis increase MLCAPE to around 400 J/kg. This should enable low-topped thunderstorms to develop ahead of the trough. Steep low-level lapse rates combined with 40 to 50 knots of flow just above the ground could be enough for marginally severe gusts. In addition, 0-3 km storm-relative helicity is expected to be near 300 m2/s2 which could also support a marginal tornado threat. The isolated severe threat is expected to be concentrated in the late morning and early afternoon as the mid-level jet moves across the region. ..Broyles/Thornton.. 12/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CST Sat Dec 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE EASTERN GULF COAST STATES AND CAROLINAS INTO FAR SOUTHERN VIRGINIA...... ...SUMMARY... Severe thunderstorms, associated with a threat for tornadoes, wind damage and hail, will be possible today from the eastern Gulf Coast northward into the Carolinas. More isolated severe storms may occur across parts of the central Appalachians and Ohio Valley. ...Southern Atlantic Coastal States... A large-scale mid-level trough will move northeastward through the Tennessee Valley and central Gulf Coast states today, as a cold front advances eastward into the southern Appalachian Mountains and eastern Gulf Coast states. At the start of the period, a line of strong thunderstorms will be ongoing from northwestern Georgia into southeast Alabama. This line could have an isolated wind-damage potential. This morning, surface temperatures will warm ahead of the line allowing for weak destabilization across much of eastern Georgia and the Carolinas. The right entrance region of the mid-level jet, associated with strong large-scale ascent, will pass over this area in conjunction with a 50 to 60 knot low-level jet. RAP forecast soundings near the jet axis have steep low-level lapse rates and 40 to 50 knots of flow just above the ground. For this reason, the more organized parts of the line should be able to easily mix the stronger winds to the surface, and result in severe wind gusts with the more intense parts of the line. Forecast soundings near the jet axis also have 0-3 km storm-relative helicity around 400 m2/s2. This will support an isolated tornado threat as well. Tornadoes will be most likely with rotating storms that develop within the line in areas that destabilize the most. The threat is expected to continue into the early to mid afternoon as the line moves into central North Carolina and eastern South Carolina. ...Central Appalachians/Ohio Valley... A mid-level large-scale trough and an associated surface low will move northeastward into the Ohio Valley today. An 80 to 90 knot mid-level jet will accompany the trough, spreading strong large-scale ascent across the region. Immediately ahead of the system, some surface heating will take place today across the Virginias and Ohio, where an axis of weak instability is expected to develop. RAP forecast soundings by early afternoon near the instability axis increase MLCAPE to around 400 J/kg. This should enable low-topped thunderstorms to develop ahead of the trough. Steep low-level lapse rates combined with 40 to 50 knots of flow just above the ground could be enough for marginally severe gusts. In addition, 0-3 km storm-relative helicity is expected to be near 300 m2/s2 which could also support a marginal tornado threat. The isolated severe threat is expected to be concentrated in the late morning and early afternoon as the mid-level jet moves across the region. ..Broyles/Thornton.. 12/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CST Sat Dec 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE EASTERN GULF COAST STATES AND CAROLINAS INTO FAR SOUTHERN VIRGINIA...... ...SUMMARY... Severe thunderstorms, associated with a threat for tornadoes, wind damage and hail, will be possible today from the eastern Gulf Coast northward into the Carolinas. More isolated severe storms may occur across parts of the central Appalachians and Ohio Valley. ...Southern Atlantic Coastal States... A large-scale mid-level trough will move northeastward through the Tennessee Valley and central Gulf Coast states today, as a cold front advances eastward into the southern Appalachian Mountains and eastern Gulf Coast states. At the start of the period, a line of strong thunderstorms will be ongoing from northwestern Georgia into southeast Alabama. This line could have an isolated wind-damage potential. This morning, surface temperatures will warm ahead of the line allowing for weak destabilization across much of eastern Georgia and the Carolinas. The right entrance region of the mid-level jet, associated with strong large-scale ascent, will pass over this area in conjunction with a 50 to 60 knot low-level jet. RAP forecast soundings near the jet axis have steep low-level lapse rates and 40 to 50 knots of flow just above the ground. For this reason, the more organized parts of the line should be able to easily mix the stronger winds to the surface, and result in severe wind gusts with the more intense parts of the line. Forecast soundings near the jet axis also have 0-3 km storm-relative helicity around 400 m2/s2. This will support an isolated tornado threat as well. Tornadoes will be most likely with rotating storms that develop within the line in areas that destabilize the most. The threat is expected to continue into the early to mid afternoon as the line moves into central North Carolina and eastern South Carolina. ...Central Appalachians/Ohio Valley... A mid-level large-scale trough and an associated surface low will move northeastward into the Ohio Valley today. An 80 to 90 knot mid-level jet will accompany the trough, spreading strong large-scale ascent across the region. Immediately ahead of the system, some surface heating will take place today across the Virginias and Ohio, where an axis of weak instability is expected to develop. RAP forecast soundings by early afternoon near the instability axis increase MLCAPE to around 400 J/kg. This should enable low-topped thunderstorms to develop ahead of the trough. Steep low-level lapse rates combined with 40 to 50 knots of flow just above the ground could be enough for marginally severe gusts. In addition, 0-3 km storm-relative helicity is expected to be near 300 m2/s2 which could also support a marginal tornado threat. The isolated severe threat is expected to be concentrated in the late morning and early afternoon as the mid-level jet moves across the region. ..Broyles/Thornton.. 12/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1159 PM CST Sat Dec 28 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE EASTERN GULF COAST STATES AND CAROLINAS INTO FAR SOUTHERN VIRGINIA...... ...SUMMARY... Severe thunderstorms, associated with a threat for tornadoes, wind damage and hail, will be possible today from the eastern Gulf Coast northward into the Carolinas. More isolated severe storms may occur across parts of the central Appalachians and Ohio Valley. ...Southern Atlantic Coastal States... A large-scale mid-level trough will move northeastward through the Tennessee Valley and central Gulf Coast states today, as a cold front advances eastward into the southern Appalachian Mountains and eastern Gulf Coast states. At the start of the period, a line of strong thunderstorms will be ongoing from northwestern Georgia into southeast Alabama. This line could have an isolated wind-damage potential. This morning, surface temperatures will warm ahead of the line allowing for weak destabilization across much of eastern Georgia and the Carolinas. The right entrance region of the mid-level jet, associated with strong large-scale ascent, will pass over this area in conjunction with a 50 to 60 knot low-level jet. RAP forecast soundings near the jet axis have steep low-level lapse rates and 40 to 50 knots of flow just above the ground. For this reason, the more organized parts of the line should be able to easily mix the stronger winds to the surface, and result in severe wind gusts with the more intense parts of the line. Forecast soundings near the jet axis also have 0-3 km storm-relative helicity around 400 m2/s2. This will support an isolated tornado threat as well. Tornadoes will be most likely with rotating storms that develop within the line in areas that destabilize the most. The threat is expected to continue into the early to mid afternoon as the line moves into central North Carolina and eastern South Carolina. ...Central Appalachians/Ohio Valley... A mid-level large-scale trough and an associated surface low will move northeastward into the Ohio Valley today. An 80 to 90 knot mid-level jet will accompany the trough, spreading strong large-scale ascent across the region. Immediately ahead of the system, some surface heating will take place today across the Virginias and Ohio, where an axis of weak instability is expected to develop. RAP forecast soundings by early afternoon near the instability axis increase MLCAPE to around 400 J/kg. This should enable low-topped thunderstorms to develop ahead of the trough. Steep low-level lapse rates combined with 40 to 50 knots of flow just above the ground could be enough for marginally severe gusts. In addition, 0-3 km storm-relative helicity is expected to be near 300 m2/s2 which could also support a marginal tornado threat. The isolated severe threat is expected to be concentrated in the late morning and early afternoon as the mid-level jet moves across the region. ..Broyles/Thornton.. 12/29/2024 Read more