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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 PM CDT Mon Apr 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS EASTWARD TO CENTRAL LOUISIANA... ...SUMMARY... Severe thunderstorms are expected from Tuesday through Wednesday morning 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... An upper low is forecast to reside over northwestern Mexico and adjacent portions of Arizona/New Mexico at the start of the period, flanked by ridging over both the western and eastern states. The low is forecast to advance steadily eastward, moving across West Texas through the second half of the period. Several lead disturbances within southwesterly/cyclonic flow ahead of this system will spread across the south-central U.S. through the period. At the surface, an outflow-reinforced warm front should reside from central Texas east-northeastward to the Louisiana/Arkansas border vicinity at the start of the period, while a rather ill-defined trough/front shifts eastward across western Texas through the day, and then becomes a bit better defined while moving across central and eventually eastern Texas through the overnight hours. ...Texas eastward to the lower Mississippi Valley... A warm-advection regime will persist across Texas through the period, shifting gradually eastward with time, ahead of the advancing upper system -- supporting broad ascent across the region. With northward advection of rich low-level Gulf moisture, beneath a plume of steep mid-level lapse rates, the aforementioned ascent will combine with abundant CAPE to support multiple rounds/widespread deep convection across the region. Given the widespread, strong-to-severe convection which likely to be ongoing from west-central Texas eastward to northern Louisiana at the start of the period, highlighting areas of greater severe potential through the day and into the evening/overnight remains quite difficult/uncertain at this time. One possible corridor of enhanced severe potential is evident across portions of southeast TX and into west LA, near roughly west-to-east outflow-reinforced surface boundary associated with ongoing, locally severe storms. Near and south of this boundary, favorably strong/veering deep-layer flow with height -- residing over the broader region -- will combine with a zone of potential heating/afternoon destabilization to support one area of concentrated severe risk. Large hail and damaging winds will be possible, along with a few tornadoes -- and some risk for a strong tornado or two -- where a few supercells are expected, especially on the southern fringe of what should be more clustered convection. Farther west, isolated convective redevelopment is expected during the afternoon and evening along the trailing outflow boundary intersection with the dryline/cold front across the central TX vicinity, and southward toward the Rio Grande. Weaker low-level shear is expected across this area, but the favorably strong flow aloft combined with mixed-layer CAPE in excess of 2000 J/kg should yield a threat for significant severe hail. Storms will spread eastward with time, with a broad area of all-hazards severe risk spreading across the eastern half of Texas and into Louisiana through the evening and overnight. Still farther west, across portions of western and northwestern TX, early-day large hail potential should subside for a time, before additional storms redevelop later into the afternoon near the mid-level low. 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 which may continue into the evening hours. ..Goss.. 04/08/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...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 1142 AM CDT Mon Apr 08 2024 Valid 081700Z - 091200Z No changes are needed to the current D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/08/2024 .PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 08 2024/ ...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. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Mon Apr 08 2024 Valid 081630Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHWEST INTO NORTH-CENTRAL/NORTHEAST TEXAS AND NORTHWEST LOUISIANA... ...SUMMARY... Multiple rounds of severe thunderstorms will develop from mid afternoon through tonight across a large portion of the southern Plains into the lower Mississippi valley. Large to giant hail will likely be the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible. ...Synopsis... Primary feature of interest related to severe potential today is a mid/upper-level trough digging over the Southwest. This feature will slowly move eastward across northern Mexico and AZ/NM through the period, while eventually evolving into a closed low. A broad zone of enhanced southwesterly flow is present downstream across northern Mexico into the southern Plains and lower/mid MS Valley. Rich low-level moisture, with surface dewpoints in the mid/upper 60s to low 70s, will continue to stream northward across much of TX through the day in tandem with a modest southerly low-level jet. A weak surface low analyzed over central OK this morning should develop northeastward this afternoon into MO, with a trailing cold front forecast to stall over parts of northwest TX into far southern OK. ...Coastal/East Texas into the Lower Mississippi Valley... A broad warm sector is already in place this morning along and south of an effective warm front. 12Z soundings from DRT/CRP show steep mid-level lapse rates, but warm low-level temperatures and related MLCIN. This, along with nebulous large-scale ascent, should act to inhibit convection for at least a couple more hours across east TX. But, continued filtered daytime heating and low-level moistening associated with the modest southerly low-level jet should encourage robust convective initiation along the northern extent of the returning moisture by early this afternoon (around 18-20Z/1pm-3pm CDT). With moderate instability and strong deep-layer shear, and elongated/nearly straight hodographs at mid/upper levels, initial supercell development will likely pose a threat for large to very large (2+ inch) hail. The tornado threat may initially be limited by modest low-level winds/shear, but the chance for a few tornadoes will likely increase through late afternoon and continue through tonight as a southerly low-level jet gradually strengthens. Additional supercells and clusters will likely spread eastward this evening and overnight along/near the warm front. While some of this activity may be slightly elevated, a continued threat for large to very large hail and tornadoes should continue overnight with embedded supercells. Severe/damaging winds may also occur with any cluster that can form. Given increased confidence in multiple rounds of supercells occurring, the Enhanced Risk for large/very large hail has been expanded eastward to include more of north-central/northeast TX and northwestern LA. ...Northwest into North-Central/Northeast Texas and Far Southern Oklahoma... Compared to locations farther east across TX, the northward return of rich low-level moisture will be delayed until later this afternoon and early evening. Still, strong daytime heating will eventually erode the cap in the vicinity of a weak front and dryline intersection across northwest TX. Ample deep-layer shear and steep mid-level lapse rates will aid in multiple robust supercells capable of producing very large to possible giant hail (2-4 inches) initially. These supercells should eventually encounter greater low-level moisture into north-central TX, with a continued threat for very large hail and a few tornadoes. The potential for a saturated temperature profile and neutral low-level lapse rates in various forecast soundings overnight along/near the warm front lowers confidence in a greater tornado threat. But, low-level shear will increase through the night, especially towards the ArkLaTex where an enhanced low-level jet should be focused. This activity may eventually merge with the low-level warm advection convection across the ArkLaTex late tonight, with messy modes possibly complicating severe hail potential. ...West/Central Texas Late Tonight/Early Tuesday Morning... Increasing forcing for ascent via stronger mid-level height falls will overspread much of west/central Texas tonight. Continued low-level moistening beneath steep mid-level lapse rates will foster moderate to strong MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail across parts of the TX Hill Country. Southerly low-level winds will also increase overnight and act to enhance initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe wind gusts and perhaps a couple tornadoes could also develop. The dryline is expected to retreat westward across parts of west Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. ..Gleason/Karstens.. 04/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Mon Apr 08 2024 Valid 081300Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHWEST AND NORTH-CENTRAL TEXAS... ...SUMMARY... Multiple rounds of severe thunderstorms should develop from mid afternoon through tonight across a large portion of the southern Plains into the Mississippi Delta region. Large to giant hail is the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible in an area extending east into northern Louisiana. ...Synopsis... Morning water-vapor imagery shows a positively-tilted mid-level trough over the Desert Southwest/northwest Mexico. This mid-level trough will amplify as it moves across the Southwest and northern Mexico. An associated belt of strong southwesterly flow will extend from the base of the trough across the southern Great Plains and into the lower MS Valley. A cyclone will develop in West Texas and deepen through the period as southerly low-level flow advects rich moisture into TX/LA [near the record high lowest 100-mb mean mixing ratio observed this early in the year at the Brownsville raob site (17.2 g/kg)]. A warm front will advance northward to the Red River by early evening. A cold front analyzed this morning moving south through the TX Panhandle/western OK will become stationary later today. ...Northwest Texas into north-central Texas... Strong heating on the northwest periphery of rich low-level moisture will weaken the cap across northwest TX by mid afternoon. Forecast soundings indicate a moderately unstable airmass (1000-2500 J/kg MLCAPE) will continue to destabilize into the evening as south-southeasterly flow strengthens and advects 50s (west) to mid 60s (near I-35) surface dewpoints into the region by early evening. Veering and strengthening flow with height (100+ kt at 250 mb) will favor supercells as the initial convective mode. Large to giant hail (3-4 inches in diameter) is possible in addition to some tornado risk towards evening. Some consolidation into a cluster/MCS may occur during the evening across north-central TX with some risk for all 3 hazards. ...East Texas into the ArkLaTex... Moderate to strong instability is expected to develop across east Texas and into western Louisiana this afternoon as upper 60s to near 70s dewpoints advect northward. Despite a solar eclipse across this region, its impact on the overall severe weather threat will likely remain minimal. Only moderate warming will be sufficient to erode inhibition across the region with a gradual strengthening of southerly 850-mb flow and isentropic ascent as the primary focus for storm development by mid to late afternoon. Strong instability and shear is expected and will support supercells capable of large to very large hail. However, there are some concerns about storm interference and updraft longevity. Initially, a warm nose around 700mb is evident on NAM/RAP forecast soundings which may limit more robust updraft development. This warm nose is forecast to erode by 23/00Z. However, by that time, widespread shower/thunderstorm development may be underway which could be a limiting factor to updraft longevity and a greater tornado/large hail threat. Some guidance suggests a MCS may develop out of the northwest/north-central Texas convection and move through northeast Texas during the overnight hours. This solution will greatly depend on the evolution of earlier convection and position of the convectively enhanced warm front by late evening. ...Texas Hill Country overnight... Increasing forcing for ascent via stronger mid-level height falls will overspread much of western/central Texas tonight. Continued moistening with mid-upper 60s deg F dewpoints beneath steep 700-500 lapse rates (8 deg C/km) will result in 2500 to 3000 J/kg MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail. Southerly 850-mb flow will increase overnight via a LLJ and act to augment initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe gusts and perhaps a tornado could develop. Have extended Slight Risk equivalent wind/tornado probabilities southward for this potential scenario. ...West Texas early Tuesday... The dryline is expected to retreat into West Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. Have adjusted the some of the severe probabilities farther west where the progged western edge of moisture/buoyancy will be located. ..Smith/Mosier.. 04/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Mon Apr 08 2024 Valid 081300Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHWEST AND NORTH-CENTRAL TEXAS... ...SUMMARY... Multiple rounds of severe thunderstorms should develop from mid afternoon through tonight across a large portion of the southern Plains into the Mississippi Delta region. Large to giant hail is the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible in an area extending east into northern Louisiana. ...Synopsis... Morning water-vapor imagery shows a positively-tilted mid-level trough over the Desert Southwest/northwest Mexico. This mid-level trough will amplify as it moves across the Southwest and northern Mexico. An associated belt of strong southwesterly flow will extend from the base of the trough across the southern Great Plains and into the lower MS Valley. A cyclone will develop in West Texas and deepen through the period as southerly low-level flow advects rich moisture into TX/LA [near the record high lowest 100-mb mean mixing ratio observed this early in the year at the Brownsville raob site (17.2 g/kg)]. A warm front will advance northward to the Red River by early evening. A cold front analyzed this morning moving south through the TX Panhandle/western OK will become stationary later today. ...Northwest Texas into north-central Texas... Strong heating on the northwest periphery of rich low-level moisture will weaken the cap across northwest TX by mid afternoon. Forecast soundings indicate a moderately unstable airmass (1000-2500 J/kg MLCAPE) will continue to destabilize into the evening as south-southeasterly flow strengthens and advects 50s (west) to mid 60s (near I-35) surface dewpoints into the region by early evening. Veering and strengthening flow with height (100+ kt at 250 mb) will favor supercells as the initial convective mode. Large to giant hail (3-4 inches in diameter) is possible in addition to some tornado risk towards evening. Some consolidation into a cluster/MCS may occur during the evening across north-central TX with some risk for all 3 hazards. ...East Texas into the ArkLaTex... Moderate to strong instability is expected to develop across east Texas and into western Louisiana this afternoon as upper 60s to near 70s dewpoints advect northward. Despite a solar eclipse across this region, its impact on the overall severe weather threat will likely remain minimal. Only moderate warming will be sufficient to erode inhibition across the region with a gradual strengthening of southerly 850-mb flow and isentropic ascent as the primary focus for storm development by mid to late afternoon. Strong instability and shear is expected and will support supercells capable of large to very large hail. However, there are some concerns about storm interference and updraft longevity. Initially, a warm nose around 700mb is evident on NAM/RAP forecast soundings which may limit more robust updraft development. This warm nose is forecast to erode by 23/00Z. However, by that time, widespread shower/thunderstorm development may be underway which could be a limiting factor to updraft longevity and a greater tornado/large hail threat. Some guidance suggests a MCS may develop out of the northwest/north-central Texas convection and move through northeast Texas during the overnight hours. This solution will greatly depend on the evolution of earlier convection and position of the convectively enhanced warm front by late evening. ...Texas Hill Country overnight... Increasing forcing for ascent via stronger mid-level height falls will overspread much of western/central Texas tonight. Continued moistening with mid-upper 60s deg F dewpoints beneath steep 700-500 lapse rates (8 deg C/km) will result in 2500 to 3000 J/kg MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail. Southerly 850-mb flow will increase overnight via a LLJ and act to augment initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe gusts and perhaps a tornado could develop. Have extended Slight Risk equivalent wind/tornado probabilities southward for this potential scenario. ...West Texas early Tuesday... The dryline is expected to retreat into West Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. Have adjusted the some of the severe probabilities farther west where the progged western edge of moisture/buoyancy will be located. ..Smith/Mosier.. 04/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Mon Apr 08 2024 Valid 081300Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHWEST AND NORTH-CENTRAL TEXAS... ...SUMMARY... Multiple rounds of severe thunderstorms should develop from mid afternoon through tonight across a large portion of the southern Plains into the Mississippi Delta region. Large to giant hail is the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible in an area extending east into northern Louisiana. ...Synopsis... Morning water-vapor imagery shows a positively-tilted mid-level trough over the Desert Southwest/northwest Mexico. This mid-level trough will amplify as it moves across the Southwest and northern Mexico. An associated belt of strong southwesterly flow will extend from the base of the trough across the southern Great Plains and into the lower MS Valley. A cyclone will develop in West Texas and deepen through the period as southerly low-level flow advects rich moisture into TX/LA [near the record high lowest 100-mb mean mixing ratio observed this early in the year at the Brownsville raob site (17.2 g/kg)]. A warm front will advance northward to the Red River by early evening. A cold front analyzed this morning moving south through the TX Panhandle/western OK will become stationary later today. ...Northwest Texas into north-central Texas... Strong heating on the northwest periphery of rich low-level moisture will weaken the cap across northwest TX by mid afternoon. Forecast soundings indicate a moderately unstable airmass (1000-2500 J/kg MLCAPE) will continue to destabilize into the evening as south-southeasterly flow strengthens and advects 50s (west) to mid 60s (near I-35) surface dewpoints into the region by early evening. Veering and strengthening flow with height (100+ kt at 250 mb) will favor supercells as the initial convective mode. Large to giant hail (3-4 inches in diameter) is possible in addition to some tornado risk towards evening. Some consolidation into a cluster/MCS may occur during the evening across north-central TX with some risk for all 3 hazards. ...East Texas into the ArkLaTex... Moderate to strong instability is expected to develop across east Texas and into western Louisiana this afternoon as upper 60s to near 70s dewpoints advect northward. Despite a solar eclipse across this region, its impact on the overall severe weather threat will likely remain minimal. Only moderate warming will be sufficient to erode inhibition across the region with a gradual strengthening of southerly 850-mb flow and isentropic ascent as the primary focus for storm development by mid to late afternoon. Strong instability and shear is expected and will support supercells capable of large to very large hail. However, there are some concerns about storm interference and updraft longevity. Initially, a warm nose around 700mb is evident on NAM/RAP forecast soundings which may limit more robust updraft development. This warm nose is forecast to erode by 23/00Z. However, by that time, widespread shower/thunderstorm development may be underway which could be a limiting factor to updraft longevity and a greater tornado/large hail threat. Some guidance suggests a MCS may develop out of the northwest/north-central Texas convection and move through northeast Texas during the overnight hours. This solution will greatly depend on the evolution of earlier convection and position of the convectively enhanced warm front by late evening. ...Texas Hill Country overnight... Increasing forcing for ascent via stronger mid-level height falls will overspread much of western/central Texas tonight. Continued moistening with mid-upper 60s deg F dewpoints beneath steep 700-500 lapse rates (8 deg C/km) will result in 2500 to 3000 J/kg MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail. Southerly 850-mb flow will increase overnight via a LLJ and act to augment initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe gusts and perhaps a tornado could develop. Have extended Slight Risk equivalent wind/tornado probabilities southward for this potential scenario. ...West Texas early Tuesday... The dryline is expected to retreat into West Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. Have adjusted the some of the severe probabilities farther west where the progged western edge of moisture/buoyancy will be located. ..Smith/Mosier.. 04/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Mon Apr 08 2024 Valid 081300Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHWEST AND NORTH-CENTRAL TEXAS... ...SUMMARY... Multiple rounds of severe thunderstorms should develop from mid afternoon through tonight across a large portion of the southern Plains into the Mississippi Delta region. Large to giant hail is the main threat, especially over northwest Texas, though a few tornadoes and severe gusts are also possible in an area extending east into northern Louisiana. ...Synopsis... Morning water-vapor imagery shows a positively-tilted mid-level trough over the Desert Southwest/northwest Mexico. This mid-level trough will amplify as it moves across the Southwest and northern Mexico. An associated belt of strong southwesterly flow will extend from the base of the trough across the southern Great Plains and into the lower MS Valley. A cyclone will develop in West Texas and deepen through the period as southerly low-level flow advects rich moisture into TX/LA [near the record high lowest 100-mb mean mixing ratio observed this early in the year at the Brownsville raob site (17.2 g/kg)]. A warm front will advance northward to the Red River by early evening. A cold front analyzed this morning moving south through the TX Panhandle/western OK will become stationary later today. ...Northwest Texas into north-central Texas... Strong heating on the northwest periphery of rich low-level moisture will weaken the cap across northwest TX by mid afternoon. Forecast soundings indicate a moderately unstable airmass (1000-2500 J/kg MLCAPE) will continue to destabilize into the evening as south-southeasterly flow strengthens and advects 50s (west) to mid 60s (near I-35) surface dewpoints into the region by early evening. Veering and strengthening flow with height (100+ kt at 250 mb) will favor supercells as the initial convective mode. Large to giant hail (3-4 inches in diameter) is possible in addition to some tornado risk towards evening. Some consolidation into a cluster/MCS may occur during the evening across north-central TX with some risk for all 3 hazards. ...East Texas into the ArkLaTex... Moderate to strong instability is expected to develop across east Texas and into western Louisiana this afternoon as upper 60s to near 70s dewpoints advect northward. Despite a solar eclipse across this region, its impact on the overall severe weather threat will likely remain minimal. Only moderate warming will be sufficient to erode inhibition across the region with a gradual strengthening of southerly 850-mb flow and isentropic ascent as the primary focus for storm development by mid to late afternoon. Strong instability and shear is expected and will support supercells capable of large to very large hail. However, there are some concerns about storm interference and updraft longevity. Initially, a warm nose around 700mb is evident on NAM/RAP forecast soundings which may limit more robust updraft development. This warm nose is forecast to erode by 23/00Z. However, by that time, widespread shower/thunderstorm development may be underway which could be a limiting factor to updraft longevity and a greater tornado/large hail threat. Some guidance suggests a MCS may develop out of the northwest/north-central Texas convection and move through northeast Texas during the overnight hours. This solution will greatly depend on the evolution of earlier convection and position of the convectively enhanced warm front by late evening. ...Texas Hill Country overnight... Increasing forcing for ascent via stronger mid-level height falls will overspread much of western/central Texas tonight. Continued moistening with mid-upper 60s deg F dewpoints beneath steep 700-500 lapse rates (8 deg C/km) will result in 2500 to 3000 J/kg MUCAPE. Elongated hodographs with 60-kt effective shear will promote supercells and mainly a risk for large to very large hail. Southerly 850-mb flow will increase overnight via a LLJ and act to augment initially limited hodographs. If a cluster organizes overnight (06-12z), a risk for severe gusts and perhaps a tornado could develop. Have extended Slight Risk equivalent wind/tornado probabilities southward for this potential scenario. ...West Texas early Tuesday... The dryline is expected to retreat into West Texas overnight with strong instability building back to near Midland early Tuesday morning. As strong upper forcing overspreads this region, at least isolated to scattered storms will probably develop on the western periphery of a strongly unstable/sheared environment. Have adjusted the some of the severe probabilities farther west where the progged western edge of moisture/buoyancy will be located. ..Smith/Mosier.. 04/08/2024 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