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WW 0010 Status Updates
STATUS REPORT ON WW 10 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 N ESF TO 50 NNW GWO TO 30 E JBR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0052 ..DEAN..01/12/24 ATTN...WFO...LZK...JAN...SHV...MEG... STATUS REPORT FOR WT 10 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC017-121440- AR . ARKANSAS COUNTIES INCLUDED ARE CHICOT LAC035-041-065-083-107-123-121440- LA . LOUISIANA PARISHES INCLUDED ARE EAST CARROLL FRANKLIN MADISON RICHLAND TENSAS WEST CARROLL MSC003-007-009-013-015-017-019-021-025-033-043-049-051-053-055- 057-069-071-075-079-081-083-087-089-093-095-097-099-101-103-105- 107-115-117-119-121-123-125-133-135-137-139-141-145-149-151-155- 159-161-163-121440- MS Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 AM CST Fri Jan 12 2024 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL/NORTHERN MISSISSIPPI AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorm winds and a few tornadoes are possible across a large part of the Southeast through early this evening. The most intense gusts (potentially above 70 mph) are possible through midday over parts of the Mid-South and Tennessee Valley regions. ...Synopsis... Broadly cyclonic flow in mid/upper levels will cover most of the CONUS through the period, except for shortwave ridging on either side of a strong lead trough now over the central/southern Plains. That perturbation will be the primary upper-air influence on convection today. The southern part -- initially located over portions of OK and north TX -- should eject northeastward to the IN/MI border area by 00Z, while the northern part moves more slowly across IA toward the Quad Cities. Overnight, these will combine into a 500-mb cyclone over Lower MI to Lake Huron, increasingly stacked on the surface cyclone described below. The 11Z surface analysis showed an area of low pressure over central MO, along the northern segment of a cold front extending across parts of central/western AR to central TX. A synoptic warm front was drawn from the low across the lower Ohio Valley. A prefrontal trough/wind shift and remnant of a Pacific front was evident over central LA southwestward to deep south TX. The surface low should occlude and move northeastward to near ORD by 00Z, then across Lower MI overnight. The main/Arctic cold front is forecast by 00Z to overtake the Pacific boundary and reach WV, the western Carolinas, northern/western GA, central/eastern FL Panhandle, and the central Gulf. The front should move offshore from the Mid-Atlantic, Carolinas and GA by 12Z, extending southwestward over central/ southwestern peninsular FL. ...Southeastern CONUS... Ongoing lines of strong to severe thunderstorms near the Mississippi River should consolidate and sweep eastward across parts of the Mid South toward the Tennessee Valley region through midday -- in and near the 30% wind/"enhanced" area. This activity will pose a threat for severe gusts (some significant/65+ kt), a few embedded tornadoes, and isolated, marginally severe hail. See SPC tornado watch 10 and related mesoscale discussions for near-term coverage of this convective stage. Though peak intensity of the main thunderstorm line is likely to be in the next several hours, as it encounters the greatest warm-sector theta-e, some severe-wind and tornado threat may persist eastward across portions of AL/GA today and into the Carolinas this evening following very strong low-level warm/theta-e advection. Additional strong-severe thunderstorm development is possible over the warm sector throughout today into this evening, as convergence lines produce showers that can grow gradually deeper and upscale. Given the strength of the wind fields projected to spread over the warm sector and ahead of the main line, some of this activity may become supercellular, also with a tornado/damaging-wind/marginal-hail threat. Dewpoints generally reaching the 50s to mid 60s F just prior to cold frontal passage, and sufficient surface-based instability, should develop today in the warm sector to offset weak midlevel lapse rates and support 500-1500 J/kg MLCAPE -- more southward, and mainly south of I-20 in AL/GA and from the Piedmont eastward in SC/NC. Forecast soundings suggest hodographs will be straightening/losing size, but remaining very long, as the buoyant layer lowers closer to the surface and the main belt of convection approaches. Still, that supports effective SRH locally exceeding 400 J/kg, amidst 60-80-kt effective-shear magnitudes. The main limiting factor for areal severe potential will be lack of greater instability. Given the strength of ambient flow, a broad 15% wind area is maintained, with the understanding that localized pockets of denser wind/tornado potential may quickly evolve within. Farther north across northern TN/KY to southern VA, though MLCAPE will be weak, intense wind fields and associated convective momentum transfer still will support some potential for convective gusts to penetrate near-neutral stability layers and reach the surface. A broad area of 60-110-kt winds in the 850-700-mb layer will shift northeastward across parts of TN/KY and the southern Appalachians today. The severe potential in such scenarios is rather spotty and nebulous, and may extend well northward within cool surface air on an isolated basis. ..Edwards/Dean.. 01/12/2024 Read more

WW 0010 Status Updates
STATUS REPORT ON WW 10 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 S IER TO 40 ESE SHV TO 35 NE LLQ TO JBR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0052 ..DEAN..01/12/24 ATTN...WFO...LZK...JAN...SHV...MEG... STATUS REPORT FOR WT 10 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC003-017-035-037-077-107-123-121340- AR . ARKANSAS COUNTIES INCLUDED ARE ASHLEY CHICOT CRITTENDEN CROSS LEE PHILLIPS ST. FRANCIS LAC013-021-035-041-049-061-065-067-069-073-083-107-111-123-127- 121340- LA . LOUISIANA PARISHES INCLUDED ARE BIENVILLE CALDWELL EAST CARROLL FRANKLIN JACKSON LINCOLN MADISON MOREHOUSE NATCHITOCHES OUACHITA RICHLAND TENSAS UNION WEST CARROLL WINN Read more

WW 0010 Status Updates
STATUS REPORT ON WW 10 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NE LFK TO 15 N SHV TO 30 WSW PBF TO 15 SW BVX. ..DEAN..01/12/24 ATTN...WFO...LZK...JAN...SHV...MEG... STATUS REPORT FOR WT 10 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC001-003-011-013-017-025-035-037-041-043-069-077-079-085-095- 107-117-123-139-145-147-121240- AR . ARKANSAS COUNTIES INCLUDED ARE ARKANSAS ASHLEY BRADLEY CALHOUN CHICOT CLEVELAND CRITTENDEN CROSS DESHA DREW JEFFERSON LEE LINCOLN LONOKE MONROE PHILLIPS PRAIRIE ST. FRANCIS UNION WHITE WOODRUFF LAC013-015-017-021-027-031-035-041-049-061-065-067-069-073-081- 083-107-111-119-123-127-121240- LA . LOUISIANA PARISHES INCLUDED ARE BIENVILLE BOSSIER CADDO CALDWELL CLAIBORNE DE SOTO EAST CARROLL FRANKLIN JACKSON LINCOLN MADISON MOREHOUSE Read more

MD 0050 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR NORTHERN LA...SOUTHEAST AR...SOUTHWEST TN...CENTRAL/NORTHERN MS
Mesoscale Discussion 0050 NWS Storm Prediction Center Norman OK 0333 AM CST Fri Jan 12 2024 Areas affected...Northern LA...Southeast AR...Southwest TN...central/northern MS Concerning...Severe potential...Tornado Watch likely Valid 120933Z - 121100Z Probability of Watch Issuance...95 percent SUMMARY...Tornado Watch issuance is likely by 4 AM CST, as storms begin to approach the region from the west. DISCUSSION...As a powerful mid/upper-level shortwave trough moves across the southern Plains early this morning, ongoing convection near the ArkLaTex region is expected to accelerate eastward. A surface cyclone is expected to consolidate later this morning near the ArkLaMiss area and then rapidly intensify as a 100+ kt midlevel jet impinges upon the region. As this occurs, 60s F dewpoints are expected to advance as far as northern MS, accompanied by an increase in MLCAPE to near 500 J/kg in areas that are currently rather cool/stable. While there will be some tendency for convection to eventually outpace low-level moisture return, organized convection is expected to reach parts of northern/central MS and perhaps southwest TN later this morning. Low-level flow/shear is already strong (as noted on regional VWPs), and a further increase is expected with time as 1-3 km AGL flow strengthens into the 60-80 kt range. The fast-moving convective line within this favorable kinematic environment will pose a threat for severe gusts (potentially in excess of 65 kt) and some potential for line-embedded tornadoes. With upstream WW 9 scheduled to expire at 4 AM CST, new tornado watch issuance across the region is likely soon. ..Dean/Edwards.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...JAN...LZK...SHV... LAT...LON 31979310 33799143 34909073 35199038 35308906 35078833 34808823 34278826 33778834 32588856 32258973 32109217 31979310 Read more

MD 0049 CONCERNING TORNADO WATCH 9... FOR NORTHEAST TX...NORTHWEST LA...CENTRAL/SOUTHERN AR
Mesoscale Discussion 0049 NWS Storm Prediction Center Norman OK 0241 AM CST Fri Jan 12 2024 Areas affected...Northeast TX...Northwest LA...central/southern AR Concerning...Tornado Watch 9... Valid 120841Z - 121015Z The severe weather threat for Tornado Watch 9 continues. SUMMARY...Some increase in the severe threat is expected with time. All severe hazards are possible. New watch issuance is likely before the expiration of Tornado Watch 9. DISCUSSION...Extensive convection is ongoing at 0830 UTC from northeast TX into AR, in advance of a strong mid/upper-level shortwave trough moving across north TX. Low-level moisture continues to gradually increase across the effective warm sector, with MLCAPE currently in the 1000-1500 J/kg range. As a 100+ kt midlevel jet associated with the approaching shortwave impinges upon the ArkLaTex region, already-favorable deep-layer flow/shear will continue to increase, and increasingly organized/sustained storm structures are expected to evolve through the morning. Discrete cells have struggled to mature in advance of the main convective line thus far, though a couple prefrontal supercells may evolve with time, with an attendant threat of all severe hazards. Otherwise, the severe-wind threat is expected to increase as the primary convective line accelerates eastward through the morning. Strong low-level flow/shear will support some threat for significant (65+ kt) gusts, as well as some potential for line-embedded tornadoes. With WW 9 scheduled to expire at 4 AM CST and some severe threat likely to spread well downstream, new watch issuance is likely for parts of the MCD area a little later this morning. ..Dean/Edwards.. 01/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... LAT...LON 31199642 32749531 33599457 34789348 35169278 35229186 35189145 34879127 34289147 33499182 32579262 32109340 31749423 31469502 31199642 Read more

WW 0010 Status Updates
STATUS REPORT ON WW 8 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 SSW APF TO 40 WNW PBI TO 30 NE VRB. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0042 ..LYONS..01/10/24 ATTN...WFO...MFL...MLB... STATUS REPORT FOR WT 8 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC021-051-085-099-100340- FL . FLORIDA COUNTIES INCLUDED ARE COLLIER HENDRY MARTIN PALM BEACH AMZ555-650-100340- CW . ADJACENT COASTAL WATERS INCLUDED ARE SEBASTIAN INLET TO JUPITER INLET 0-20 NM COASTAL WATERS FROM JUPITER INLET TO DEERFIELD BEACH FL OUT 20 NM THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0010 Status Updates
STATUS REPORT ON WW 8 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 SSW APF TO 40 WNW PBI TO 30 NE VRB. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0042 ..LYONS..01/10/24 ATTN...WFO...MFL...MLB... STATUS REPORT FOR WT 8 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC021-051-085-099-100340- FL . FLORIDA COUNTIES INCLUDED ARE COLLIER HENDRY MARTIN PALM BEACH AMZ555-650-100340- CW . ADJACENT COASTAL WATERS INCLUDED ARE SEBASTIAN INLET TO JUPITER INLET 0-20 NM COASTAL WATERS FROM JUPITER INLET TO DEERFIELD BEACH FL OUT 20 NM THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0336 AM CST Fri Jan 12 2024 Valid 151200Z - 201200Z ...DISCUSSION... Upper-level mean troughing will persist across much of the CONUS during the Day 4-8 period. At least one reinforcing surge of cold, arctic air associated with this pattern will maintain a dry and/or stable airmass for much of the U.S., and thunderstorm chances are expected to be low. Some modest Gulf return flow may occur near the end of the period in the Day 7/8-Thu/Fri time period as an upper ridge builds over the West and a shortwave impulse migrates east from the High Plains to the Southeast. However, quality low-level moisture will likely remain offshore in the absence of stronger surface cyclogenesis, precluding severe thunderstorm potential. Read more