Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0143 AM CST Fri Dec 01 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... A deepening trough and associated belt of increased mid-level flow will continue to drive the weather across much of the CONUS today. Strong west-southwesterly flow aloft across the southern Rockies will favor breezy downslope winds across the High Plains, though relative humidity will remain around 30-40 percent. This in combination with cooler temperatures and moist fuels will keep fire concerns low. Further west, surface high pressure building across the Great Basin will bring offshore flow across portions of Southern California. Very strong winds are likely in the morning hours across the mountains in Santa Barbra and Ventura counties. Relative humidity will remain above thresholds for concern despite strong winds. Localized Elevated fire weather will be possible in the afternoon across favored downslope regions, where afternoon minimum relative humidity around 20-30 percent may overlap sustained winds 20-25 mph. Given the localized nature of this threat and generally cool forecast temperatures, no areas were included with this outlook. ..Thornton.. 12/01/2023 ...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 0143 AM CST Fri Dec 01 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... A deepening trough and associated belt of increased mid-level flow will continue to drive the weather across much of the CONUS today. Strong west-southwesterly flow aloft across the southern Rockies will favor breezy downslope winds across the High Plains, though relative humidity will remain around 30-40 percent. This in combination with cooler temperatures and moist fuels will keep fire concerns low. Further west, surface high pressure building across the Great Basin will bring offshore flow across portions of Southern California. Very strong winds are likely in the morning hours across the mountains in Santa Barbra and Ventura counties. Relative humidity will remain above thresholds for concern despite strong winds. Localized Elevated fire weather will be possible in the afternoon across favored downslope regions, where afternoon minimum relative humidity around 20-30 percent may overlap sustained winds 20-25 mph. Given the localized nature of this threat and generally cool forecast temperatures, no areas were included with this outlook. ..Thornton.. 12/01/2023 ...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 0143 AM CST Fri Dec 01 2023 Valid 011200Z - 021200Z ...NO CRITICAL AREAS... ...Synopsis... A deepening trough and associated belt of increased mid-level flow will continue to drive the weather across much of the CONUS today. Strong west-southwesterly flow aloft across the southern Rockies will favor breezy downslope winds across the High Plains, though relative humidity will remain around 30-40 percent. This in combination with cooler temperatures and moist fuels will keep fire concerns low. Further west, surface high pressure building across the Great Basin will bring offshore flow across portions of Southern California. Very strong winds are likely in the morning hours across the mountains in Santa Barbra and Ventura counties. Relative humidity will remain above thresholds for concern despite strong winds. Localized Elevated fire weather will be possible in the afternoon across favored downslope regions, where afternoon minimum relative humidity around 20-30 percent may overlap sustained winds 20-25 mph. Given the localized nature of this threat and generally cool forecast temperatures, no areas were included with this outlook. ..Thornton.. 12/01/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2295 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR COASTAL SOUTHWEST/SOUTH-CENTRAL LA
Mesoscale Discussion 2295 NWS Storm Prediction Center Norman OK 1131 PM CST Thu Nov 30 2023 Areas affected...Coastal southwest/south-central LA Concerning...Severe potential...Watch unlikely Valid 010531Z - 010730Z Probability of Watch Issuance...5 percent SUMMARY...A low-probability threat for a brief tornado along with isolated strong gusts of 40-55 mph will likely persist overnight, but within a spatially confined area of a single parish or two at any one time that should gradually shift east. DISCUSSION...Attempts at brief mesovortex formation appeared to have a relative peak during the 03-04Z time frame before thunderstorm clusters became more oriented from southwest to northeast across far southwest LA. This type of orientation within the low-level warm theta-e advection regime should support a rather limited spatial extent of brief tornado potential at any one time during the early morning. The overlap of upper 60s surface dew points within warm-sector inflow where surface winds have not yet veered appears spatially small, and is presently confined to eastern Cameron Parish. With convection likely regenerating in this southwest-northeast orientation through much of the night, this favorable warm-sector inflow region and resultant brief tornado threat should slowly shift east along the coastal parishes of southwest to south-central LA. ..Grams/Smith.. 12/01/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LIX...LCH... LAT...LON 30179264 30229208 30159165 30049133 29849112 29589112 29369128 29399174 29529284 29769315 29929313 30179264 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Fri Dec 01 2023 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST... ...SUMMARY... Isolated marginally severe storms will be possible on Saturday over parts of the Southeast. ...Southeast... A trough at mid-levels will move eastward through the Great Plains on Saturday, with flow remaining southwesterly across the eastern half of the U.S. Ahead of this system, a moist airmass will be in place from the central Gulf Coast states eastward to the southern Atlantic Seaboard. A cold front is forecast to advance southeastward into the central Gulf Coast states by afternoon. Ahead of the front, lift associated with a 40 to 50 knot low-level jet will support scattered thunderstorm development. Although some of the storms will be elevated, surface-based convection will be possible during the day into early evening from the central Gulf Coast northeastward into southwest Georgia. An isolated potential for strong wind gusts or a tornado will be possible within this corridor. The severe threat is expected to remain marginal. ..Broyles.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1137 PM CST Thu Nov 30 2023 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL GULF STATES... ...SUMMARY... Scattered storms, with some severe potential, are possible over parts of the central Gulf Coast states. ...Gulf States... Strong, negative-tilt short-wave trough is ejecting northeast across OK late this evening. This feature will advance into the lower OH Valley early in the period as a 90kt 500mb speed max translates toward western KY by daybreak. Farther west, a digging short-wave trough will approach the southern Rockies by 02/00z before shifting slowly toward the High Plains. This evolution will result in weak midlevel height rises across the Gulf States as the strongest core of 500mb flow extends from west TX-southern MO-OH Valley. At the surface, primary synoptic front is forecast to move off the TX Coast, extending across the lower MS Valley. This wind shift will gradually advance southeast, but do so slowly due to the lack of upper support, and a relatively weak surface high centered over northern MO. Additionally, while low-level warm advection will be maximized early over the central Gulf States, some increase in the LLJ is expected across the northwestern Gulf Basin into southern LA/southern MS during the latter half of the period. In the absence of meaningful large-scale support, and only partial boundary-layer heating, it appears low-level warm advection will prove instrumental in convective development much of the period. Forecast soundings across the warm sector suggest modest buoyancy will develop across southern LA into southern AL/extreme western FL Panhandle. Scattered convection that evolves within this air mass will do so within a sheared environment favorable for organized updrafts -- potentially supercellular. Where surface dew points are able to rise to near 70F, there is some risk for surface-based updrafts; otherwise, much of the convection across this region will be slightly elevated. Latest guidance suggests several bouts of potentially robust convection, both early and overnight, modulated by the LLJ. Gusty winds and perhaps a brief tornado are the primary risks. ..Darrow/Thornton.. 12/01/2023 Read more

MD 2294 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR SOUTHEAST TX AND SOUTHWEST LA
Mesoscale Discussion 2294 NWS Storm Prediction Center Norman OK 0652 PM CST Thu Nov 30 2023 Areas affected...Far southeast TX and southwest LA Concerning...Severe potential...Watch unlikely Valid 010052Z - 010245Z Probability of Watch Issuance...20 percent SUMMARY...A spatially limited threat for a tornado should persist along a portion of the northwest Gulf Coast this evening. DISCUSSION...A deep convective cluster has become confined to the far southeast three counties of TX (Chambers, Jefferson, and Orange). This convection has struggled to organize beyond sporadic attempts at lower-end/transient mid-level rotation. The overall thermodynamic environment, which has been the primary mitigating factor to severe weather thus far, might become slightly more conducive to generating a surface-based supercell as temperatures have warmed into the upper 60s near/just south of this activity along the immediate coast. This should gradually translate east through the rest of the evening into southwest LA, improving upon the nil instability sampled in the 00Z LCH sounding. While the low-level wind profile has been in the process of strengthening over the past few hours, resulting in increasingly enlarged hodographs, confidence remains low that sustained supercell development will occur as depicted in the 23Z RRFS compared to the negligible signal in the 00Z WoFS. ..Grams/Smith.. 12/01/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LCH...HGX... LAT...LON 30249413 30369376 30349328 30249298 30089289 29909290 29769299 29739308 29679349 29599407 29549447 29649457 29699457 30249413 Read more

MD 2293 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHWESTERN OKLAHOMA INTO NORTH-CENTRAL TEXAS
Mesoscale Discussion 2293 NWS Storm Prediction Center Norman OK 0525 PM CST Thu Nov 30 2023 Areas affected...southwestern Oklahoma into north-central Texas Concerning...Severe potential...Watch unlikely Valid 302325Z - 010100Z Probability of Watch Issuance...5 percent SUMMARY...A marginal risk of severe hail will be possible over the next couple of hours. DISCUSSION...Recent radar trends have shown strengthening cores within the cells near the Red River along the Texas/Oklahoma border. Mid-level cooling associated with the upper-level trough has given way to a small corridor of MLCAPE around 500 J/kg along the OK/TX border. Forecast soundings from the RAP along with objective analysis show steep mid-level lapse rates around 7-7.5 c/km and deep layer shear around 35-40 kts. This will support potential for a few instances of severe hail (up to 1-1.25 in). Recent reports of hail up to 3/4 inch have been noted near Childress. Due to short time window within the better instability and due to nocturnal cooling, it is unlikely that the hail threat will be long lived. As such, a watch is not anticipated. ..Thornton/Smith.. 11/30/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...OUN...LUB...AMA... LAT...LON 34000016 34350024 34710018 34860011 34930010 35069999 35209954 35139900 34969849 34749825 34369801 34189793 33929795 33519813 33419917 33569977 34000016 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0648 PM CST Thu Nov 30 2023 Valid 010100Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS INTO SOUTHERN LOUISIANA... ...SUMMARY... A few severe storms/tornadoes remain possible tonight from southeast Texas into southern Louisiana. Isolated hail is also possible across southern Oklahoma into northeast Texas. ...01z Update... Early-evening water-vapor imagery depicts a well-defined short-wave trough over the southern High Plains, ejecting northeast in line with earlier model guidance. Seasonally cold 500mb temperatures (less than -20C) are spreading across western OK/northwestern TX which is contributing to elevated buoyancy for parcels lifted above the boundary layer. 00z sounding from OUN exhibited steep 3-6km lapse rates and MUCAPE around 400 J/kg. Marginally severe hail appears possible with convection immediately ahead of the ejecting vort/short wave. Farther southeast along the upper TX Coast, deep-layer flow is beginning to veer which has shunted the primary zone of confluence for deep convection just east of the Houston metro region. Latest radar data suggests the most robust updrafts are noted along the southwestern flank of a southwest-northeast line that extends from the lower Sabine River Valley toward Galveston Bay. This is likely due to higher dew points/buoyancy along the western fringe of the strongest low-level warm advection. Current thinking is warm advection will continue to be the primary instigator in thunderstorm activity along the upper TX/southwestern LA Coast tonight as the main zone of strong midlevel height falls will spread well north of this region. Greatest potential for a tornado or two will occur with near-surface-based storms in proximity to greater SRH, which is now east of Houston. Even so, the tornado threat should remain isolated. ..Darrow.. 12/01/2023 Read more