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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Mon Apr 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...D4/Thursday... A full-latitude mid/upper trough should be centered on the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A cyclogentic surface low in the Mid-South vicinity should further deepen as it tracks into southern Ontario by early Friday. Dual areas of relatively greater severe potential are evident. Fast 850-700 mb winds should be coincident with mid to upper 60s surface dew points from north FL into the Carolinas. While mid-level lapse rates will be weak and stronger boundary-layer heating is confined to FL, adequate warming should occur ahead of a convective band to foster at least a damaging wind/brief tornado threat from late morning into the afternoon. Over the Upper OH Valley vicinity, a synoptically favorable corridor of organized severe may develop just ahead of the deepening surface cyclone. Primary uncertainty is with the actual spatial extent of any severe threat that can develop midday into the afternoon, given a moderate amount of spread in timing the cyclone track. For now, have highlighted the overall consensus region where the combination of weak buoyancy and a meridional supercell wind profile appears most probable. ...D8/Monday... Air mass modification will ensue northward from the western Gulf towards the weekend. Indications of the next shortwave trough ejecting eastward in the West should increase severe potential into parts of the Plains around early next week. 00Z deterministic guidance provide an illusion of consistency for next Monday afternoon/evening from the southern High to the central Great Plains. However, spread within respective ensembles and run-to-run consistency of individual control members are too large to warrant a highlight beyond an area-of-interest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Mon Apr 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...D4/Thursday... A full-latitude mid/upper trough should be centered on the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A cyclogentic surface low in the Mid-South vicinity should further deepen as it tracks into southern Ontario by early Friday. Dual areas of relatively greater severe potential are evident. Fast 850-700 mb winds should be coincident with mid to upper 60s surface dew points from north FL into the Carolinas. While mid-level lapse rates will be weak and stronger boundary-layer heating is confined to FL, adequate warming should occur ahead of a convective band to foster at least a damaging wind/brief tornado threat from late morning into the afternoon. Over the Upper OH Valley vicinity, a synoptically favorable corridor of organized severe may develop just ahead of the deepening surface cyclone. Primary uncertainty is with the actual spatial extent of any severe threat that can develop midday into the afternoon, given a moderate amount of spread in timing the cyclone track. For now, have highlighted the overall consensus region where the combination of weak buoyancy and a meridional supercell wind profile appears most probable. ...D8/Monday... Air mass modification will ensue northward from the western Gulf towards the weekend. Indications of the next shortwave trough ejecting eastward in the West should increase severe potential into parts of the Plains around early next week. 00Z deterministic guidance provide an illusion of consistency for next Monday afternoon/evening from the southern High to the central Great Plains. However, spread within respective ensembles and run-to-run consistency of individual control members are too large to warrant a highlight beyond an area-of-interest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Mon Apr 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...D4/Thursday... A full-latitude mid/upper trough should be centered on the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A cyclogentic surface low in the Mid-South vicinity should further deepen as it tracks into southern Ontario by early Friday. Dual areas of relatively greater severe potential are evident. Fast 850-700 mb winds should be coincident with mid to upper 60s surface dew points from north FL into the Carolinas. While mid-level lapse rates will be weak and stronger boundary-layer heating is confined to FL, adequate warming should occur ahead of a convective band to foster at least a damaging wind/brief tornado threat from late morning into the afternoon. Over the Upper OH Valley vicinity, a synoptically favorable corridor of organized severe may develop just ahead of the deepening surface cyclone. Primary uncertainty is with the actual spatial extent of any severe threat that can develop midday into the afternoon, given a moderate amount of spread in timing the cyclone track. For now, have highlighted the overall consensus region where the combination of weak buoyancy and a meridional supercell wind profile appears most probable. ...D8/Monday... Air mass modification will ensue northward from the western Gulf towards the weekend. Indications of the next shortwave trough ejecting eastward in the West should increase severe potential into parts of the Plains around early next week. 00Z deterministic guidance provide an illusion of consistency for next Monday afternoon/evening from the southern High to the central Great Plains. However, spread within respective ensembles and run-to-run consistency of individual control members are too large to warrant a highlight beyond an area-of-interest. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Mon Apr 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...D4/Thursday... A full-latitude mid/upper trough should be centered on the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A cyclogentic surface low in the Mid-South vicinity should further deepen as it tracks into southern Ontario by early Friday. Dual areas of relatively greater severe potential are evident. Fast 850-700 mb winds should be coincident with mid to upper 60s surface dew points from north FL into the Carolinas. While mid-level lapse rates will be weak and stronger boundary-layer heating is confined to FL, adequate warming should occur ahead of a convective band to foster at least a damaging wind/brief tornado threat from late morning into the afternoon. Over the Upper OH Valley vicinity, a synoptically favorable corridor of organized severe may develop just ahead of the deepening surface cyclone. Primary uncertainty is with the actual spatial extent of any severe threat that can develop midday into the afternoon, given a moderate amount of spread in timing the cyclone track. For now, have highlighted the overall consensus region where the combination of weak buoyancy and a meridional supercell wind profile appears most probable. ...D8/Monday... Air mass modification will ensue northward from the western Gulf towards the weekend. Indications of the next shortwave trough ejecting eastward in the West should increase severe potential into parts of the Plains around early next week. 00Z deterministic guidance provide an illusion of consistency for next Monday afternoon/evening from the southern High to the central Great Plains. However, spread within respective ensembles and run-to-run consistency of individual control members are too large to warrant a highlight beyond an area-of-interest. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Mon Apr 08 2024 Valid 101200Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms are expected on Wednesday into Wednesday night across parts of the Gulf Coast States and Deep South. Tornadoes, some strong, and damaging winds should be the primary hazards. ...Synopsis... Primary feature of interest will be a southern-stream shortwave trough over the west TX vicinity at 12Z Wednesday. This shortwave impulse should phase into a broader amplified trough being carved out as a northern-stream wave digs into the Upper Midwest. This will yield substantial flow amplification through the troposphere, commencing by Wednesday afternoon as a surface cyclone deepens northeastward from southeast TX across the Mid-South. ...Central Gulf Coast to the Deep South... Widespread convection is expected to be ongoing from the Sabine to Lower MS Valleys vicinity at 12Z Wednesday. Some guidance suggests a plume of moderately steep mid-level lapse rates will still be present ahead of this activity back into the northwest Gulf. A surge of richer Gulf moisture is progged to advect north-northeast just ahead of the morning activity, yielding moderate buoyancy across at least south-southeast LA. Convective intensity should diurnally increase by late morning/midday within already strong low-level shear. The initial thermodynamic environment coupled with further strengthening of tropospheric wind fields should yield a threat for strong supercells through the afternoon, generating in the LA to south MS vicinity and spreading northeastward. Eventually in time and with north/east extent, an increasingly limited thermodynamic environment, through both weaker mid and low-level lapse rates and deep convection regenerating southwestward towards buoyancy plume, should curtail a more widespread severe threat. Still, given the very strong low-level winds by Wednesday night, a conditional high-shear/low-CAPE tornado environment should remain present where surface dew points can reach at least into the mid 60s. ..Grams.. 04/08/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Mon Apr 08 2024 Valid 101200Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms are expected on Wednesday into Wednesday night across parts of the Gulf Coast States and Deep South. Tornadoes, some strong, and damaging winds should be the primary hazards. ...Synopsis... Primary feature of interest will be a southern-stream shortwave trough over the west TX vicinity at 12Z Wednesday. This shortwave impulse should phase into a broader amplified trough being carved out as a northern-stream wave digs into the Upper Midwest. This will yield substantial flow amplification through the troposphere, commencing by Wednesday afternoon as a surface cyclone deepens northeastward from southeast TX across the Mid-South. ...Central Gulf Coast to the Deep South... Widespread convection is expected to be ongoing from the Sabine to Lower MS Valleys vicinity at 12Z Wednesday. Some guidance suggests a plume of moderately steep mid-level lapse rates will still be present ahead of this activity back into the northwest Gulf. A surge of richer Gulf moisture is progged to advect north-northeast just ahead of the morning activity, yielding moderate buoyancy across at least south-southeast LA. Convective intensity should diurnally increase by late morning/midday within already strong low-level shear. The initial thermodynamic environment coupled with further strengthening of tropospheric wind fields should yield a threat for strong supercells through the afternoon, generating in the LA to south MS vicinity and spreading northeastward. Eventually in time and with north/east extent, an increasingly limited thermodynamic environment, through both weaker mid and low-level lapse rates and deep convection regenerating southwestward towards buoyancy plume, should curtail a more widespread severe threat. Still, given the very strong low-level winds by Wednesday night, a conditional high-shear/low-CAPE tornado environment should remain present where surface dew points can reach at least into the mid 60s. ..Grams.. 04/08/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Mon Apr 08 2024 Valid 101200Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms are expected on Wednesday into Wednesday night across parts of the Gulf Coast States and Deep South. Tornadoes, some strong, and damaging winds should be the primary hazards. ...Synopsis... Primary feature of interest will be a southern-stream shortwave trough over the west TX vicinity at 12Z Wednesday. This shortwave impulse should phase into a broader amplified trough being carved out as a northern-stream wave digs into the Upper Midwest. This will yield substantial flow amplification through the troposphere, commencing by Wednesday afternoon as a surface cyclone deepens northeastward from southeast TX across the Mid-South. ...Central Gulf Coast to the Deep South... Widespread convection is expected to be ongoing from the Sabine to Lower MS Valleys vicinity at 12Z Wednesday. Some guidance suggests a plume of moderately steep mid-level lapse rates will still be present ahead of this activity back into the northwest Gulf. A surge of richer Gulf moisture is progged to advect north-northeast just ahead of the morning activity, yielding moderate buoyancy across at least south-southeast LA. Convective intensity should diurnally increase by late morning/midday within already strong low-level shear. The initial thermodynamic environment coupled with further strengthening of tropospheric wind fields should yield a threat for strong supercells through the afternoon, generating in the LA to south MS vicinity and spreading northeastward. Eventually in time and with north/east extent, an increasingly limited thermodynamic environment, through both weaker mid and low-level lapse rates and deep convection regenerating southwestward towards buoyancy plume, should curtail a more widespread severe threat. Still, given the very strong low-level winds by Wednesday night, a conditional high-shear/low-CAPE tornado environment should remain present where surface dew points can reach at least into the mid 60s. ..Grams.. 04/08/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Mon Apr 08 2024 Valid 101200Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms are expected on Wednesday into Wednesday night across parts of the Gulf Coast States and Deep South. Tornadoes, some strong, and damaging winds should be the primary hazards. ...Synopsis... Primary feature of interest will be a southern-stream shortwave trough over the west TX vicinity at 12Z Wednesday. This shortwave impulse should phase into a broader amplified trough being carved out as a northern-stream wave digs into the Upper Midwest. This will yield substantial flow amplification through the troposphere, commencing by Wednesday afternoon as a surface cyclone deepens northeastward from southeast TX across the Mid-South. ...Central Gulf Coast to the Deep South... Widespread convection is expected to be ongoing from the Sabine to Lower MS Valleys vicinity at 12Z Wednesday. Some guidance suggests a plume of moderately steep mid-level lapse rates will still be present ahead of this activity back into the northwest Gulf. A surge of richer Gulf moisture is progged to advect north-northeast just ahead of the morning activity, yielding moderate buoyancy across at least south-southeast LA. Convective intensity should diurnally increase by late morning/midday within already strong low-level shear. The initial thermodynamic environment coupled with further strengthening of tropospheric wind fields should yield a threat for strong supercells through the afternoon, generating in the LA to south MS vicinity and spreading northeastward. Eventually in time and with north/east extent, an increasingly limited thermodynamic environment, through both weaker mid and low-level lapse rates and deep convection regenerating southwestward towards buoyancy plume, should curtail a more widespread severe threat. Still, given the very strong low-level winds by Wednesday night, a conditional high-shear/low-CAPE tornado environment should remain present where surface dew points can reach at least into the mid 60s. ..Grams.. 04/08/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0147 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE TEXAS BIG BEND... ...Synopsis... A mid-level low will move across northern Mexico and the Southwest and into Texas on Tuesday. South of this low, strong mid-level flow will overspread a deeply mixed airmass across Far West Texas and Southwest Texas. This will result in 20 to 25 mph sustained surface winds and single digit relative humidity. Large fires are possible in this region, and a cold front will bring a wind shift during the evening which could lead to erratic fire behavior on any ongoing fires. ..Bentley.. 04/08/2024 ...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 0147 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE TEXAS BIG BEND... ...Synopsis... A mid-level low will move across northern Mexico and the Southwest and into Texas on Tuesday. South of this low, strong mid-level flow will overspread a deeply mixed airmass across Far West Texas and Southwest Texas. This will result in 20 to 25 mph sustained surface winds and single digit relative humidity. Large fires are possible in this region, and a cold front will bring a wind shift during the evening which could lead to erratic fire behavior on any ongoing fires. ..Bentley.. 04/08/2024 ...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 0147 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE TEXAS BIG BEND... ...Synopsis... A mid-level low will move across northern Mexico and the Southwest and into Texas on Tuesday. South of this low, strong mid-level flow will overspread a deeply mixed airmass across Far West Texas and Southwest Texas. This will result in 20 to 25 mph sustained surface winds and single digit relative humidity. Large fires are possible in this region, and a cold front will bring a wind shift during the evening which could lead to erratic fire behavior on any ongoing fires. ..Bentley.. 04/08/2024 ...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 0147 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE TEXAS BIG BEND... ...Synopsis... A mid-level low will move across northern Mexico and the Southwest and into Texas on Tuesday. South of this low, strong mid-level flow will overspread a deeply mixed airmass across Far West Texas and Southwest Texas. This will result in 20 to 25 mph sustained surface winds and single digit relative humidity. Large fires are possible in this region, and a cold front will bring a wind shift during the evening which could lead to erratic fire behavior on any ongoing fires. ..Bentley.. 04/08/2024 ...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 0146 AM CDT Mon Apr 08 2024 Valid 081200Z - 091200Z ...Synopsis... A mid-level trough will amplify across the Southwest and northern Mexico during the day today. Meanwhile, a surface cyclone will develop in West Texas. A deeply mixed atmosphere is expected across much of the Southwest which will result in stronger mid-level flow mixing to the surface. Winds of 15 to 20 mph are expected across southern New Mexico and Far West Texas with relative humidity in the single digits. Removed the Critical area from the prior Day 2 as forecast guidance continues to trend weaker with surface winds across southeast New Mexico. ..Bentley.. 04/08/2024 ...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 0146 AM CDT Mon Apr 08 2024 Valid 081200Z - 091200Z ...Synopsis... A mid-level trough will amplify across the Southwest and northern Mexico during the day today. Meanwhile, a surface cyclone will develop in West Texas. A deeply mixed atmosphere is expected across much of the Southwest which will result in stronger mid-level flow mixing to the surface. Winds of 15 to 20 mph are expected across southern New Mexico and Far West Texas with relative humidity in the single digits. Removed the Critical area from the prior Day 2 as forecast guidance continues to trend weaker with surface winds across southeast New Mexico. ..Bentley.. 04/08/2024 ...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 0146 AM CDT Mon Apr 08 2024 Valid 081200Z - 091200Z ...Synopsis... A mid-level trough will amplify across the Southwest and northern Mexico during the day today. Meanwhile, a surface cyclone will develop in West Texas. A deeply mixed atmosphere is expected across much of the Southwest which will result in stronger mid-level flow mixing to the surface. Winds of 15 to 20 mph are expected across southern New Mexico and Far West Texas with relative humidity in the single digits. Removed the Critical area from the prior Day 2 as forecast guidance continues to trend weaker with surface winds across southeast New Mexico. ..Bentley.. 04/08/2024 ...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 0146 AM CDT Mon Apr 08 2024 Valid 081200Z - 091200Z ...Synopsis... A mid-level trough will amplify across the Southwest and northern Mexico during the day today. Meanwhile, a surface cyclone will develop in West Texas. A deeply mixed atmosphere is expected across much of the Southwest which will result in stronger mid-level flow mixing to the surface. Winds of 15 to 20 mph are expected across southern New Mexico and Far West Texas with relative humidity in the single digits. Removed the Critical area from the prior Day 2 as forecast guidance continues to trend weaker with surface winds across southeast New Mexico. ..Bentley.. 04/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX TO WEST LA... ...SUMMARY... Severe thunderstorms are expected from Tuesday into early morning Wednesday across most of Texas towards the Lower Mississippi River Valley. Several tornadoes, a couple of which should be strong, significant large hail, and damaging winds are likely. ...Synopsis... A shortwave trough centered near the AZ/NM/northwest Mexico border area at 12Z Tuesday will progress steadily eastward into west TX by early Wednesday. Two separate mid-level speed maxes, one curling through the base of the trough and another farther east closer to the northwest Gulf Coastal Plain will gradually translate eastward, likely phasing by 12Z Wednesday. As this occurs, multiple surface lows should consolidate into a primary cyclone in the southeast TX vicinity early Wednesday. ...TX/LA... Several rounds of deep convection are expected across a large portion of TX towards the Ark-La-Tex and Lower MS Valley vicinity during the period. A corridor of enhanced severe potential is evident across a part of southeast TX into west LA, where the environment should be most favorable for regenerative supercells and organized clustering. An MCS will likely be ongoing at 12Z Tuesday in the Ark-La-Tex to Ark-La-Miss vicinity with scattered to widespread convection trailing westward into west TX. An isolated supercell or two may be ongoing in the south-central TX area as well. Primary convective coverage during the day will be tied to the persistent low-level warm theta-e advection regime, with regenerative periods of convection expected across at least east TX to the Ark-La-Miss. Surface heating of a richly moist Gulf air mass to the south of the convective plume, coupled with steep mid-level lapse rates from 8-9 C/km should support a broad swath of moderate to large buoyancy by afternoon. This will yield an uptick in severe storms in a portion of southeast TX to west LA. Although convective mode should predominately consist of clusters, embedded supercells are expected within a favorable low-level hodograph and deep-layer shear, supporting all severe hazards. Farther west, isolated convective redevelopment should occur during the early evening along the trailing outflow boundary intersection with the dryline/surface trough in the central TX vicinity. Low-level shear should be substantially weaker relative to the Sabine Valley, but the favorable deep shear/thermodynamic environment should yield a threat for significant severe hail. An increase in storm coverage is expected Tuesday night across south-central TX to southwest LA. Overall tornado potential should be centered on the Sabine Valley, with potential for discrete warm-sector supercells merging into the residual large-scale outflow boundary. A couple strong tornadoes will be possible. Finally, in west TX, early-day large hail potential should subside for a time, before additional storms refire later into the afternoon near the mid-level trough. While surface winds should largely be northerly by this time, adequate buoyancy within the approaching mid-level cold pocket will yield a renewed threat for large hail. This should wane after dusk. ...Lower Great Lakes... The drifting mid/upper low over the Upper Great Lakes/northern Ontario will aid in scattered showers and lower-topped thunderstorms across the Lower Great Lakes vicinity on Tuesday afternoon. A plume of low-level moisture being advected northeast from the Lower MS Valley, coupled with differential boundary-layer heating south of the stratocu field attendant to the northwest Ontario surface cyclone, should yield a plume of MLCAPE around 500 J/kg. Adequate speed shear within the deep-layer southwesterly flow regime should support a threat for isolated severe hail and locally strong gusts. ..Grams.. 04/08/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX TO WEST LA... ...SUMMARY... Severe thunderstorms are expected from Tuesday into early morning Wednesday across most of Texas towards the Lower Mississippi River Valley. Several tornadoes, a couple of which should be strong, significant large hail, and damaging winds are likely. ...Synopsis... A shortwave trough centered near the AZ/NM/northwest Mexico border area at 12Z Tuesday will progress steadily eastward into west TX by early Wednesday. Two separate mid-level speed maxes, one curling through the base of the trough and another farther east closer to the northwest Gulf Coastal Plain will gradually translate eastward, likely phasing by 12Z Wednesday. As this occurs, multiple surface lows should consolidate into a primary cyclone in the southeast TX vicinity early Wednesday. ...TX/LA... Several rounds of deep convection are expected across a large portion of TX towards the Ark-La-Tex and Lower MS Valley vicinity during the period. A corridor of enhanced severe potential is evident across a part of southeast TX into west LA, where the environment should be most favorable for regenerative supercells and organized clustering. An MCS will likely be ongoing at 12Z Tuesday in the Ark-La-Tex to Ark-La-Miss vicinity with scattered to widespread convection trailing westward into west TX. An isolated supercell or two may be ongoing in the south-central TX area as well. Primary convective coverage during the day will be tied to the persistent low-level warm theta-e advection regime, with regenerative periods of convection expected across at least east TX to the Ark-La-Miss. Surface heating of a richly moist Gulf air mass to the south of the convective plume, coupled with steep mid-level lapse rates from 8-9 C/km should support a broad swath of moderate to large buoyancy by afternoon. This will yield an uptick in severe storms in a portion of southeast TX to west LA. Although convective mode should predominately consist of clusters, embedded supercells are expected within a favorable low-level hodograph and deep-layer shear, supporting all severe hazards. Farther west, isolated convective redevelopment should occur during the early evening along the trailing outflow boundary intersection with the dryline/surface trough in the central TX vicinity. Low-level shear should be substantially weaker relative to the Sabine Valley, but the favorable deep shear/thermodynamic environment should yield a threat for significant severe hail. An increase in storm coverage is expected Tuesday night across south-central TX to southwest LA. Overall tornado potential should be centered on the Sabine Valley, with potential for discrete warm-sector supercells merging into the residual large-scale outflow boundary. A couple strong tornadoes will be possible. Finally, in west TX, early-day large hail potential should subside for a time, before additional storms refire later into the afternoon near the mid-level trough. While surface winds should largely be northerly by this time, adequate buoyancy within the approaching mid-level cold pocket will yield a renewed threat for large hail. This should wane after dusk. ...Lower Great Lakes... The drifting mid/upper low over the Upper Great Lakes/northern Ontario will aid in scattered showers and lower-topped thunderstorms across the Lower Great Lakes vicinity on Tuesday afternoon. A plume of low-level moisture being advected northeast from the Lower MS Valley, coupled with differential boundary-layer heating south of the stratocu field attendant to the northwest Ontario surface cyclone, should yield a plume of MLCAPE around 500 J/kg. Adequate speed shear within the deep-layer southwesterly flow regime should support a threat for isolated severe hail and locally strong gusts. ..Grams.. 04/08/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX TO WEST LA... ...SUMMARY... Severe thunderstorms are expected from Tuesday into early morning Wednesday across most of Texas towards the Lower Mississippi River Valley. Several tornadoes, a couple of which should be strong, significant large hail, and damaging winds are likely. ...Synopsis... A shortwave trough centered near the AZ/NM/northwest Mexico border area at 12Z Tuesday will progress steadily eastward into west TX by early Wednesday. Two separate mid-level speed maxes, one curling through the base of the trough and another farther east closer to the northwest Gulf Coastal Plain will gradually translate eastward, likely phasing by 12Z Wednesday. As this occurs, multiple surface lows should consolidate into a primary cyclone in the southeast TX vicinity early Wednesday. ...TX/LA... Several rounds of deep convection are expected across a large portion of TX towards the Ark-La-Tex and Lower MS Valley vicinity during the period. A corridor of enhanced severe potential is evident across a part of southeast TX into west LA, where the environment should be most favorable for regenerative supercells and organized clustering. An MCS will likely be ongoing at 12Z Tuesday in the Ark-La-Tex to Ark-La-Miss vicinity with scattered to widespread convection trailing westward into west TX. An isolated supercell or two may be ongoing in the south-central TX area as well. Primary convective coverage during the day will be tied to the persistent low-level warm theta-e advection regime, with regenerative periods of convection expected across at least east TX to the Ark-La-Miss. Surface heating of a richly moist Gulf air mass to the south of the convective plume, coupled with steep mid-level lapse rates from 8-9 C/km should support a broad swath of moderate to large buoyancy by afternoon. This will yield an uptick in severe storms in a portion of southeast TX to west LA. Although convective mode should predominately consist of clusters, embedded supercells are expected within a favorable low-level hodograph and deep-layer shear, supporting all severe hazards. Farther west, isolated convective redevelopment should occur during the early evening along the trailing outflow boundary intersection with the dryline/surface trough in the central TX vicinity. Low-level shear should be substantially weaker relative to the Sabine Valley, but the favorable deep shear/thermodynamic environment should yield a threat for significant severe hail. An increase in storm coverage is expected Tuesday night across south-central TX to southwest LA. Overall tornado potential should be centered on the Sabine Valley, with potential for discrete warm-sector supercells merging into the residual large-scale outflow boundary. A couple strong tornadoes will be possible. Finally, in west TX, early-day large hail potential should subside for a time, before additional storms refire later into the afternoon near the mid-level trough. While surface winds should largely be northerly by this time, adequate buoyancy within the approaching mid-level cold pocket will yield a renewed threat for large hail. This should wane after dusk. ...Lower Great Lakes... The drifting mid/upper low over the Upper Great Lakes/northern Ontario will aid in scattered showers and lower-topped thunderstorms across the Lower Great Lakes vicinity on Tuesday afternoon. A plume of low-level moisture being advected northeast from the Lower MS Valley, coupled with differential boundary-layer heating south of the stratocu field attendant to the northwest Ontario surface cyclone, should yield a plume of MLCAPE around 500 J/kg. Adequate speed shear within the deep-layer southwesterly flow regime should support a threat for isolated severe hail and locally strong gusts. ..Grams.. 04/08/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX TO WEST LA... ...SUMMARY... Severe thunderstorms are expected from Tuesday into early morning Wednesday across most of Texas towards the Lower Mississippi River Valley. Several tornadoes, a couple of which should be strong, significant large hail, and damaging winds are likely. ...Synopsis... A shortwave trough centered near the AZ/NM/northwest Mexico border area at 12Z Tuesday will progress steadily eastward into west TX by early Wednesday. Two separate mid-level speed maxes, one curling through the base of the trough and another farther east closer to the northwest Gulf Coastal Plain will gradually translate eastward, likely phasing by 12Z Wednesday. As this occurs, multiple surface lows should consolidate into a primary cyclone in the southeast TX vicinity early Wednesday. ...TX/LA... Several rounds of deep convection are expected across a large portion of TX towards the Ark-La-Tex and Lower MS Valley vicinity during the period. A corridor of enhanced severe potential is evident across a part of southeast TX into west LA, where the environment should be most favorable for regenerative supercells and organized clustering. An MCS will likely be ongoing at 12Z Tuesday in the Ark-La-Tex to Ark-La-Miss vicinity with scattered to widespread convection trailing westward into west TX. An isolated supercell or two may be ongoing in the south-central TX area as well. Primary convective coverage during the day will be tied to the persistent low-level warm theta-e advection regime, with regenerative periods of convection expected across at least east TX to the Ark-La-Miss. Surface heating of a richly moist Gulf air mass to the south of the convective plume, coupled with steep mid-level lapse rates from 8-9 C/km should support a broad swath of moderate to large buoyancy by afternoon. This will yield an uptick in severe storms in a portion of southeast TX to west LA. Although convective mode should predominately consist of clusters, embedded supercells are expected within a favorable low-level hodograph and deep-layer shear, supporting all severe hazards. Farther west, isolated convective redevelopment should occur during the early evening along the trailing outflow boundary intersection with the dryline/surface trough in the central TX vicinity. Low-level shear should be substantially weaker relative to the Sabine Valley, but the favorable deep shear/thermodynamic environment should yield a threat for significant severe hail. An increase in storm coverage is expected Tuesday night across south-central TX to southwest LA. Overall tornado potential should be centered on the Sabine Valley, with potential for discrete warm-sector supercells merging into the residual large-scale outflow boundary. A couple strong tornadoes will be possible. Finally, in west TX, early-day large hail potential should subside for a time, before additional storms refire later into the afternoon near the mid-level trough. While surface winds should largely be northerly by this time, adequate buoyancy within the approaching mid-level cold pocket will yield a renewed threat for large hail. This should wane after dusk. ...Lower Great Lakes... The drifting mid/upper low over the Upper Great Lakes/northern Ontario will aid in scattered showers and lower-topped thunderstorms across the Lower Great Lakes vicinity on Tuesday afternoon. A plume of low-level moisture being advected northeast from the Lower MS Valley, coupled with differential boundary-layer heating south of the stratocu field attendant to the northwest Ontario surface cyclone, should yield a plume of MLCAPE around 500 J/kg. Adequate speed shear within the deep-layer southwesterly flow regime should support a threat for isolated severe hail and locally strong gusts. ..Grams.. 04/08/2024 Read more