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MD 2291 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEAST TEXAS INTO FAR SOUTHEASTERN OKLAHOMA
Mesoscale Discussion 2291 NWS Storm Prediction Center Norman OK 1244 PM CST Thu Nov 30 2023 Areas affected...Northeast Texas into far southwestern Oklahoma Concerning...Severe potential...Watch unlikely Valid 301844Z - 302045Z Probability of Watch Issuance...5 percent SUMMARY...The potential for isolated severe hail, and perhaps damaging wind gusts, should increase through the mid-afternoon hours across northeast Texas and portions of far southwestern Oklahoma. Watch issuance is not expected. DISCUSSION...Over the past hour, the coverage and intensity of convection has increased across central to northeast TX as lift within a warm advection regime and ahead of an approaching upper wave increases. While much of this convection is well displaced from a narrow plume of surface-based buoyancy stretching from the TX Gulf coast into central TX, MUCAPE across northeast TX has steadily increased to around 1000 J/kg amid warming/moistening within the 925-850 mb layer. Observed storm motions and a lack of apparent low-level mesocyclones further suggest that this convection is rooted above the surface, but elongated hodographs above 2 km (featuring effective bulk shear values near 40 knots), should support storm organization with an attendant risk of isolated large hail. Cooling cloud top temperatures and an uptick in lightning counts over the past 15-30 minutes suggest convection is beginning to realize this environment, so an increasing hail threat seems probable (though clustered storm modes may inhibit the overall threat). Recent hi-res guidance, including HRRR-based SCRAMM solutions and WOFS ensemble output, appears to have picked up on this trend and shows increasing potential for isolated hail across northeast TX over the next several hours. While the signal for severe winds is comparatively weaker, a few damaging gusts will be possible. Regardless, the overall severe threat should remain too limited to warrant watch issuance. ..Moore/Thompson.. 11/30/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SHV...TSA...HGX...FWD...OUN... LAT...LON 31409742 31779765 32809746 33529748 33949761 34369566 34179495 33879449 33059425 32399443 31749489 31529539 31409742 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CST Thu Nov 30 2023 Valid 302000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHWEST LOUISIANA... ...SUMMARY... A few severe storms/tornadoes are possible through tonight from southeast Texas into southern Louisiana. Farther north, isolated hail and strong wind gusts will also be possible across parts of East/North Texas and southern Oklahoma. ...20z Update... The only changes with the 20z update were to trim the western edges of the outlook area based on latest observation trends and location of current convection. Widespread cloud cover and scattered convection has limited heating, and combined with poor low-level lapse rates, low-level inhibition is limited surface-based storm development. Some stronger storms may still develop this evening near the Sabine River as the surface cold front tracks southeast. However, overall severe potential will likely remain somewhat subdued due to poor thermodynamics despite favorable vertical shear. ..Leitman.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1025 AM CST Thu Nov 30 2023/ ...Northwest Gulf coast and southern Plains through tonight... Thunderstorms are forming this morning over southeast TX from Matagorda Bay northeastward through the Houston area to Toledo Bend reservoir. The convection appears to be driven by low-level warm advection, as well as a subtle/lead speed max ejecting aloft, in advance of the primary shortwave trough over NM. Observed and forecast hodographs (with substantial length and curvature) across southeast TX look favorable for right-moving supercells with some tornado potential. However, with widespread cloud cover and warm advection being the primary mode of storm initiation, the updrafts may be rooted slightly above the ground. Thus, the convection may not take full advantage of the shear profiles, compared to a more favorable scenario where fully surface-based storms formed in a warmer environment upstream and moved into the environment expected across southeast TX/upper TX coast this afternoon/evening. Regardless, there will be some potential for supercells and a few tornadoes given the strong low-level shear in a moistening/gradually destabilizing environment, with the aforementioned caveats related to poor low-level lapse rates. This threat will slowly increase across southeast TX/upper TX coast through the afternoon and continue through tonight while spreading eastward into southwest/south central LA. Farther northwest, elevated thunderstorm development is expected from central/north TX into southern OK, in the zone of ascent preceding the primary shortwave trough that will begin to move east-northeastward this afternoon from NM toward OK and north TX. The strongest of these storms will pose some threat for marginally severe hail based on some steepening of midlevel lapse rates and relatively long hodographs aloft. A narrow zone of buoyancy rooted near the surface may develop later this afternoon from western north TX into extreme southwest OK, near the primary surface cyclone. However, the main forcing for ascent will be east/northeast of this zone by late afternoon, and forecast hodographs reflect low-midlevel wave passage with a pronounced veer-back signature relatively close to the ground (as low as 1 km AGL). Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 11/30/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Thu Nov 30 2023/ ...Synopsis... A belt of strong west-southwesterly flow aloft will persist across the southern Rockies, favoring continued breezy downslope flow over the southern High Plains. Similar to Day 1/Thursday, marginal RH (25-30 percent) should mitigate most fire-weather concerns here. Farther west, surface high pressure will build into the Great Basin, yielding an offshore pressure gradient over southern CA. While breezy/gusty north-northeasterly surface winds may support locally elevated fire-weather conditions (primarily over parts of Santa Barbara, Ventura, and Los Angeles Counties), fairly cool surface temperatures will limit RH reductions and the overall fire-weather risk. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2290 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHEAST TX
Mesoscale Discussion 2290 NWS Storm Prediction Center Norman OK 1159 AM CST Thu Nov 30 2023 Areas affected...Southeast TX Concerning...Severe potential...Watch possible Valid 301759Z - 302000Z Probability of Watch Issuance...40 percent SUMMARY...The tornado threat may gradually increase with time through the day. Eventual watch issuance is possible, though timing is uncertain. DISCUSSION...Convection is gradually increasing across parts of southeast TX within a low-level warm-advection regime, with recent satellite and radar trends indicating an increase in storm intensity southwest of Galveston Bay. Mid/upper 60s F dewpoints are gradually streaming northward across the region, though widespread cloudiness and increasing precipitation will continue to limit heating and destabilization through the afternoon. The timing and extent of surface-based supercell development this afternoon remain uncertain, and may continue to be limited by weak low-level lapse rates and buoyancy. However, it remains possible that consolidation of the stronger ongoing elevated convection may result in transient supercell development, and there is also some potential for a supercell or two to develop offshore and move inland later this afternoon. Favorable low-level and deep-layer shear (as noted on the TIAH/THOU VWPs) will support a conditional tornado risk if any mature supercells can evolve with time. Tornado watch issuance is possible sometime this afternoon, if observational trends begin to support imminent supercell potential. ..Dean/Thompson.. 11/30/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LCH...HGX...CRP... LAT...LON 28639647 29129651 29409613 29869520 30139443 29829409 29559411 29319446 29099484 28849533 28689568 28549599 28439619 28369631 28639647 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL GULF COAST VICINITY... ...SUMMARY... Scattered storms, some severe, are possible over parts of the central Gulf Coast states on Friday into Friday night. ...Synopsis... A low-level warm advection regime will persist across the central Gulf Coast/Southeast vicinity on Friday. This is in response to a midlevel shortwave trough and surface low moving across the Midwest. A trailing cold front extending from the low across eastern/southern TX early in the period will shift slowly east toward the Mid-South/Lower MS Valley vicinity. Mid/upper 60s F surface dewpoints will develop northward across MS/AL through the day. Showers and cloud cover will limit heating and the overall lapse rate environment will remain poor. This will result in mainly weak destabilization as far north as the I-20 corridor, though greater instability (to around 1000 J/kg MLCAPE) will remain confined to the coastal vicinity. Nevertheless, vertically veering wind profiles and effective shear magnitudes greater than 35 kt will support at least transient organized cells. Stronger forcing for ascent will remain focused north of the region, with low-level confluence along the effective surface front contributing to bands of showers/thunderstorms shifting east through the period. Given shear profiles conditionally supporting supercells, but a rather modest thermodynamic environment, will maintain the Marginal (level 1 of 5) risk with some southward adjustments based on latest forecast guidance. ..Leitman.. 11/30/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL GULF COAST VICINITY... ...SUMMARY... Scattered storms, some severe, are possible over parts of the central Gulf Coast states on Friday into Friday night. ...Synopsis... A low-level warm advection regime will persist across the central Gulf Coast/Southeast vicinity on Friday. This is in response to a midlevel shortwave trough and surface low moving across the Midwest. A trailing cold front extending from the low across eastern/southern TX early in the period will shift slowly east toward the Mid-South/Lower MS Valley vicinity. Mid/upper 60s F surface dewpoints will develop northward across MS/AL through the day. Showers and cloud cover will limit heating and the overall lapse rate environment will remain poor. This will result in mainly weak destabilization as far north as the I-20 corridor, though greater instability (to around 1000 J/kg MLCAPE) will remain confined to the coastal vicinity. Nevertheless, vertically veering wind profiles and effective shear magnitudes greater than 35 kt will support at least transient organized cells. Stronger forcing for ascent will remain focused north of the region, with low-level confluence along the effective surface front contributing to bands of showers/thunderstorms shifting east through the period. Given shear profiles conditionally supporting supercells, but a rather modest thermodynamic environment, will maintain the Marginal (level 1 of 5) risk with some southward adjustments based on latest forecast guidance. ..Leitman.. 11/30/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL GULF COAST VICINITY... ...SUMMARY... Scattered storms, some severe, are possible over parts of the central Gulf Coast states on Friday into Friday night. ...Synopsis... A low-level warm advection regime will persist across the central Gulf Coast/Southeast vicinity on Friday. This is in response to a midlevel shortwave trough and surface low moving across the Midwest. A trailing cold front extending from the low across eastern/southern TX early in the period will shift slowly east toward the Mid-South/Lower MS Valley vicinity. Mid/upper 60s F surface dewpoints will develop northward across MS/AL through the day. Showers and cloud cover will limit heating and the overall lapse rate environment will remain poor. This will result in mainly weak destabilization as far north as the I-20 corridor, though greater instability (to around 1000 J/kg MLCAPE) will remain confined to the coastal vicinity. Nevertheless, vertically veering wind profiles and effective shear magnitudes greater than 35 kt will support at least transient organized cells. Stronger forcing for ascent will remain focused north of the region, with low-level confluence along the effective surface front contributing to bands of showers/thunderstorms shifting east through the period. Given shear profiles conditionally supporting supercells, but a rather modest thermodynamic environment, will maintain the Marginal (level 1 of 5) risk with some southward adjustments based on latest forecast guidance. ..Leitman.. 11/30/2023 Read more