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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CST Thu Jan 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEASTERN U.S. GULF COAST... ...SUMMARY... Isolated severe thunderstorms may occur Friday afternoon through early Saturday morning across southern Louisiana, Mississippi, Alabama, and the Florida Panhandle. ...Coastal Southeast... A large -- but weakening -- upper trough is forecast to sweep eastward across the central/southern Plains during the day Friday, and then continue eastward across the southeastern quarter of the country into the overnight hours. As this occurs, an attendant surface low is forecast to shift eastward across the Gulf Coast region, along a surface baroclinic zone expected to lift very slowly northward across the northern Gulf, and potentially/eventually inland into coastal areas. A preceding cool/continental airmass inland will be slow to retreat, with elevated/warm-advection precipitation likely to evolve north of the warm front which should further impede inland advance of the boundary. Still, models continue to suggest weak surface-based destabilization will occur across coastal counties, within a narrow window just ahead of the advancing low, mainly through late afternoon and into the overnight hours, from southeastern Louisiana eastward to the Florida Panhandle. While elevated showers and thunderstorms are expected well north of the surface front, any severe risk will likely be confined to coastal areas just ahead of the low, near and perhaps just north of the surface warm front. While limited instability should temper severe risk, strong/veering winds with height will provide a favorable kinematic environment for conditional supercell potential. As such, a couple of tornadoes remain possible across this region, along with risk for locally strong/damaging wind gusts. Risk will shift from west to east with time, reaching the Florida Big Bend area by sunrise Saturday. ..Goss.. 01/04/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CST Thu Jan 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEASTERN U.S. GULF COAST... ...SUMMARY... Isolated severe thunderstorms may occur Friday afternoon through early Saturday morning across southern Louisiana, Mississippi, Alabama, and the Florida Panhandle. ...Coastal Southeast... A large -- but weakening -- upper trough is forecast to sweep eastward across the central/southern Plains during the day Friday, and then continue eastward across the southeastern quarter of the country into the overnight hours. As this occurs, an attendant surface low is forecast to shift eastward across the Gulf Coast region, along a surface baroclinic zone expected to lift very slowly northward across the northern Gulf, and potentially/eventually inland into coastal areas. A preceding cool/continental airmass inland will be slow to retreat, with elevated/warm-advection precipitation likely to evolve north of the warm front which should further impede inland advance of the boundary. Still, models continue to suggest weak surface-based destabilization will occur across coastal counties, within a narrow window just ahead of the advancing low, mainly through late afternoon and into the overnight hours, from southeastern Louisiana eastward to the Florida Panhandle. While elevated showers and thunderstorms are expected well north of the surface front, any severe risk will likely be confined to coastal areas just ahead of the low, near and perhaps just north of the surface warm front. While limited instability should temper severe risk, strong/veering winds with height will provide a favorable kinematic environment for conditional supercell potential. As such, a couple of tornadoes remain possible across this region, along with risk for locally strong/damaging wind gusts. Risk will shift from west to east with time, reaching the Florida Big Bend area by sunrise Saturday. ..Goss.. 01/04/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Jan 04 2024 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 01/04/2024 .PREV DISCUSSION... /ISSUED 0132 AM CST Thu Jan 04 2024/ ...Synopsis... Fire weather concerns will be limited for today across the country. A cool continental air mass will be reinforced across the Plains and Midwest today as a cold front gradually spreads south. Across the Southeast, a dry offshore flow regime is anticipated, but seasonal temperatures will limit diurnal RH reductions, and the probability of winds exceeding elevated thresholds appears limited. Recent surface observations show a deepening low over portions of eastern AZ/western NM as an upper wave approaches the region. The passage of a Pacific cold front across southern NM/southwest TX this afternoon will likely result in strong westerly winds between 15-25 mph. However, the potential for widespread cloud cover and scattered showers limits confidence in RH values falling to near elevated thresholds over a substantially large area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Jan 04 2024 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 01/04/2024 .PREV DISCUSSION... /ISSUED 0132 AM CST Thu Jan 04 2024/ ...Synopsis... Fire weather concerns will be limited for today across the country. A cool continental air mass will be reinforced across the Plains and Midwest today as a cold front gradually spreads south. Across the Southeast, a dry offshore flow regime is anticipated, but seasonal temperatures will limit diurnal RH reductions, and the probability of winds exceeding elevated thresholds appears limited. Recent surface observations show a deepening low over portions of eastern AZ/western NM as an upper wave approaches the region. The passage of a Pacific cold front across southern NM/southwest TX this afternoon will likely result in strong westerly winds between 15-25 mph. However, the potential for widespread cloud cover and scattered showers limits confidence in RH values falling to near elevated thresholds over a substantially large area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Jan 04 2024 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 01/04/2024 .PREV DISCUSSION... /ISSUED 0132 AM CST Thu Jan 04 2024/ ...Synopsis... Fire weather concerns will be limited for today across the country. A cool continental air mass will be reinforced across the Plains and Midwest today as a cold front gradually spreads south. Across the Southeast, a dry offshore flow regime is anticipated, but seasonal temperatures will limit diurnal RH reductions, and the probability of winds exceeding elevated thresholds appears limited. Recent surface observations show a deepening low over portions of eastern AZ/western NM as an upper wave approaches the region. The passage of a Pacific cold front across southern NM/southwest TX this afternoon will likely result in strong westerly winds between 15-25 mph. However, the potential for widespread cloud cover and scattered showers limits confidence in RH values falling to near elevated thresholds over a substantially large area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Jan 04 2024 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 01/04/2024 .PREV DISCUSSION... /ISSUED 0132 AM CST Thu Jan 04 2024/ ...Synopsis... Fire weather concerns will be limited for today across the country. A cool continental air mass will be reinforced across the Plains and Midwest today as a cold front gradually spreads south. Across the Southeast, a dry offshore flow regime is anticipated, but seasonal temperatures will limit diurnal RH reductions, and the probability of winds exceeding elevated thresholds appears limited. Recent surface observations show a deepening low over portions of eastern AZ/western NM as an upper wave approaches the region. The passage of a Pacific cold front across southern NM/southwest TX this afternoon will likely result in strong westerly winds between 15-25 mph. However, the potential for widespread cloud cover and scattered showers limits confidence in RH values falling to near elevated thresholds over a substantially large area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Thu Jan 04 2024 Valid 041700Z - 051200Z ...NO CRITICAL AREAS... No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below. ..Thornton.. 01/04/2024 .PREV DISCUSSION... /ISSUED 0132 AM CST Thu Jan 04 2024/ ...Synopsis... Fire weather concerns will be limited for today across the country. A cool continental air mass will be reinforced across the Plains and Midwest today as a cold front gradually spreads south. Across the Southeast, a dry offshore flow regime is anticipated, but seasonal temperatures will limit diurnal RH reductions, and the probability of winds exceeding elevated thresholds appears limited. Recent surface observations show a deepening low over portions of eastern AZ/western NM as an upper wave approaches the region. The passage of a Pacific cold front across southern NM/southwest TX this afternoon will likely result in strong westerly winds between 15-25 mph. However, the potential for widespread cloud cover and scattered showers limits confidence in RH values falling to near elevated thresholds over a substantially large area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1012 AM CST Thu Jan 04 2024 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A pronounced mid-level trough will impinge on the Southern Plains as another mid-level trough ejects into the Atlantic today. Surface high pressure and cooler air will overspread the eastern CONUS, limiting thunderstorm potential, while low-level moisture and marginal buoyancy will return northward across parts of the south-central U.S. Cold air aloft associated with the passing mid-level trough may support isolated lightning flashes across central NM into central TX through the period. However, slightly better chances for thunderstorm development will be associated with the warm-air advection regime over the TX coastline later tonight. ..Squitieri.. 01/04/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1012 AM CST Thu Jan 04 2024 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A pronounced mid-level trough will impinge on the Southern Plains as another mid-level trough ejects into the Atlantic today. Surface high pressure and cooler air will overspread the eastern CONUS, limiting thunderstorm potential, while low-level moisture and marginal buoyancy will return northward across parts of the south-central U.S. Cold air aloft associated with the passing mid-level trough may support isolated lightning flashes across central NM into central TX through the period. However, slightly better chances for thunderstorm development will be associated with the warm-air advection regime over the TX coastline later tonight. ..Squitieri.. 01/04/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1012 AM CST Thu Jan 04 2024 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A pronounced mid-level trough will impinge on the Southern Plains as another mid-level trough ejects into the Atlantic today. Surface high pressure and cooler air will overspread the eastern CONUS, limiting thunderstorm potential, while low-level moisture and marginal buoyancy will return northward across parts of the south-central U.S. Cold air aloft associated with the passing mid-level trough may support isolated lightning flashes across central NM into central TX through the period. However, slightly better chances for thunderstorm development will be associated with the warm-air advection regime over the TX coastline later tonight. ..Squitieri.. 01/04/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1012 AM CST Thu Jan 04 2024 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A pronounced mid-level trough will impinge on the Southern Plains as another mid-level trough ejects into the Atlantic today. Surface high pressure and cooler air will overspread the eastern CONUS, limiting thunderstorm potential, while low-level moisture and marginal buoyancy will return northward across parts of the south-central U.S. Cold air aloft associated with the passing mid-level trough may support isolated lightning flashes across central NM into central TX through the period. However, slightly better chances for thunderstorm development will be associated with the warm-air advection regime over the TX coastline later tonight. ..Squitieri.. 01/04/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1012 AM CST Thu Jan 04 2024 Valid 041630Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A pronounced mid-level trough will impinge on the Southern Plains as another mid-level trough ejects into the Atlantic today. Surface high pressure and cooler air will overspread the eastern CONUS, limiting thunderstorm potential, while low-level moisture and marginal buoyancy will return northward across parts of the south-central U.S. Cold air aloft associated with the passing mid-level trough may support isolated lightning flashes across central NM into central TX through the period. However, slightly better chances for thunderstorm development will be associated with the warm-air advection regime over the TX coastline later tonight. ..Squitieri.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Thu Jan 04 2024 Valid 041300Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today or tonight. ...Synopsis... A southern-stream trough will continue eastward from the Southwest Deserts/far northwest Mexico early today toward the southern Plains by tonight. This system will include a strong, cyclonically curved mid-level speed max that will nose into western Texas during the late afternoon and evening, resulting in steepening lapse rates. Sporadic weak thunderstorms are expected today across parts of New Mexico into west/northwest Texas. ...East/Southeast Texas... Air mass modification over the western Gulf of Mexico will lead to steady low-level moistening for coastal areas late tonight into early Friday, with thunderstorm potential increasing. The primary warm sector and evolving surface wave should remain focused just off the Texas coast late tonight, although it is conceivable that a few strong near-surface-based storms/weak supercells could occur just offshore/near the middle Texas coast, with thunderstorms otherwise progressively more elevated and generally weaker inland (northward) across the remainder of east/southeast Texas. Severe probabilities do not currently appear warranted given expectations that a stable surface layer will likely persist over inland areas, but this scenario will be monitored and reevaluated in subsequent outlooks. ..Guyer/Smith.. 01/04/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Jan 04 2024 Valid 071200Z - 121200Z ...DISCUSSION... Minimal severe potential remains evident across the CONUS on Day 4/Sunday as a cold front clears much of the FL Peninsula. Another pronounced upper trough/low is forecast to eject across the southern Plains and Southeast from Day 5/Monday into Day 6/Tuesday. Low-level moisture should return northward in earnest from Sunday night into Monday ahead of this cyclone, with at least low 60s surface dewpoints probably reaching parts of east TX into southern LA by Monday afternoon. A deepening surface low is progged to develop from the TX Panhandle to the Mid-South by Tuesday morning, with associated cold front expected to sweep eastward across east TX and the lower MS Valley. There is still some uncertainty regarding how much instability will develop inland across these areas due to the possibility of substantial convection over the northern Gulf of Mexico impeding low-level moisture advection to some extent. Even so, GEFS mean forecast MLCAPE of 500-1000 J/kg from east TX into LA and southern MS/AL should be more than enough to support a severe thunderstorm threat given the presence of very strong deep-layer shear. The threat for supercells and short line segments capable of producing tornadoes, large hail, and damaging winds should spread eastward across this area from Monday afternoon through Monday night and early Tuesday morning. Some adjustments have been made to the northern and eastern extent of the 15% severe area for Monday across MS/AL and the FL Panhandle based on latest deterministic and ensemble guidance. This includes the northward extent of GEFS and EPS mean surface dewpoints reaching into at least the low 60s. A 15% severe delineation has also been introduced for Tuesday across parts of north/central FL and southern GA. This will be a continuation of the threat from Monday farther west, as the mature upper cyclone is forecast to move quickly northeastward from the lower MS Valley to the TN/OH Valley and Mid-Atlantic by Tuesday evening. Very strong mid-level flow will likely aid in ample deep-layer shear to support continued convective organization. While some concern also exists on Tuesday regarding the potential for widespread thunderstorms over the northern Gulf of Mexico, medium-range guidance remains in good agreement that mid to upper 60s surface dewpoints will likely advect northward across much of FL and into southern GA ahead of the surface cold front. Low-level shear appears strong enough for updraft rotation and a tornado threat. Very strong wind fields overall should also support a threat for severe/damaging winds as convection spreads eastward along/ahead of the front Tuesday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Jan 04 2024 Valid 071200Z - 121200Z ...DISCUSSION... Minimal severe potential remains evident across the CONUS on Day 4/Sunday as a cold front clears much of the FL Peninsula. Another pronounced upper trough/low is forecast to eject across the southern Plains and Southeast from Day 5/Monday into Day 6/Tuesday. Low-level moisture should return northward in earnest from Sunday night into Monday ahead of this cyclone, with at least low 60s surface dewpoints probably reaching parts of east TX into southern LA by Monday afternoon. A deepening surface low is progged to develop from the TX Panhandle to the Mid-South by Tuesday morning, with associated cold front expected to sweep eastward across east TX and the lower MS Valley. There is still some uncertainty regarding how much instability will develop inland across these areas due to the possibility of substantial convection over the northern Gulf of Mexico impeding low-level moisture advection to some extent. Even so, GEFS mean forecast MLCAPE of 500-1000 J/kg from east TX into LA and southern MS/AL should be more than enough to support a severe thunderstorm threat given the presence of very strong deep-layer shear. The threat for supercells and short line segments capable of producing tornadoes, large hail, and damaging winds should spread eastward across this area from Monday afternoon through Monday night and early Tuesday morning. Some adjustments have been made to the northern and eastern extent of the 15% severe area for Monday across MS/AL and the FL Panhandle based on latest deterministic and ensemble guidance. This includes the northward extent of GEFS and EPS mean surface dewpoints reaching into at least the low 60s. A 15% severe delineation has also been introduced for Tuesday across parts of north/central FL and southern GA. This will be a continuation of the threat from Monday farther west, as the mature upper cyclone is forecast to move quickly northeastward from the lower MS Valley to the TN/OH Valley and Mid-Atlantic by Tuesday evening. Very strong mid-level flow will likely aid in ample deep-layer shear to support continued convective organization. While some concern also exists on Tuesday regarding the potential for widespread thunderstorms over the northern Gulf of Mexico, medium-range guidance remains in good agreement that mid to upper 60s surface dewpoints will likely advect northward across much of FL and into southern GA ahead of the surface cold front. Low-level shear appears strong enough for updraft rotation and a tornado threat. Very strong wind fields overall should also support a threat for severe/damaging winds as convection spreads eastward along/ahead of the front Tuesday. Read more