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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0720 AM CDT Tue Apr 09 2024 Valid 091300Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR CENTRAL INTO EAST TEXAS AND WESTERN LOUISIANA... ...SUMMARY... Scattered severe thunderstorms are likely today across much of Texas into the lower Mississippi River Valley. Several tornadoes, a couple of which may be strong, large to very large hail, and severe gusts are forecast. ...Synopsis... A mid- to upper-level low evident in water-vapor imagery near the NM/AZ/Mexico border this morning, will move east into northwest TX by daybreak Wednesday. Early morning analysis indicates an outflow-reinforced effective frontal zone is draped east to west from western LA into central TX, with the western portion of the boundary intersecting a surface low over the Permian Basin this morning. This surface low will gradually develop eastward into the TX Hill Country by early evening as the mid- to upper-level trough/low encroaches on the southern Great Plains. Little overall northward advancement is forecast in the outflow/effective frontal zone across central TX eastward into north-central LA during the period. ...TX to Lower MS Valley... A multi-scenario severe thunderstorm outlook is lending considerable uncertainty to this forecast. Strong to locally severe thunderstorms may continue to develop and increase in coverage over northwest/west TX this morning as the leading edge of stronger upper forcing for ascent overspreads a capped but moist/unstable airmass near/north of the frontal zone (reference 12z Midland raob). As an 80-kt 500mb speed max translates through the base of the upper trough, additional storm development will likely occur in a moist/warm conveyor across portions of central TX eastward into western LA. Models maintain the LLJ across east TX into southern AR most of the period. As a result, episodic bouts of deep convection should be noted across this region. Strong boundary-layer heating on the southwestern periphery of active convective clusters (most likely to occur over east-central TX and locales farther east) will yield a very unstable airmass by mid afternoon. The presence of surface dewpoints near 70 deg F beneath steep 700-500 mb lapse rates will yield large buoyancy, and the risk for large to very large hail with the stronger updrafts. Large low-level hodographs (200-300 m2/s2 0-1 km SRH) in the warm frontal zone will act to enhance both supercell development and a tornado risk with any supercells that can develop and move into this moist/strong low-level shear corridor. During the evening, large-scale height falls will spread east and it seems increasingly probable a squall line will develop. A few tornadoes and 60-80 mph gusts are possible with this potential linear MCS. ...Lower Great Lakes... Southern influence of a strong short-wave trough will glance northern OH into western NY. Boundary-layer heating is expected to contribute to modest instability by mid afternoon as surface temperatures warm through the mid 60s to near 70F. Ample deep-layer shear will exist for a few robust storms capable of generating gusty winds and perhaps isolated severe hail. Greatest risk will be with convection that develops along the front as it eases southeast into this region. ..Smith/Mosier.. 04/09/2024 Read more

MD 0393 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHWEST TX INTO THE PERMIAN BASIN AND FAR SOUTHEAST NM
Mesoscale Discussion 0393 NWS Storm Prediction Center Norman OK 0530 AM CDT Tue Apr 09 2024 Areas affected...Southwest TX into the Permian Basin and Far Southeast NM Concerning...Severe potential...Watch possible Valid 091030Z - 091230Z Probability of Watch Issuance...40 percent SUMMARY...Conditional risk for large to very large hail will continue from far southeast New Mexico into the Permian Basin and southwest Texas this morning. A watch may be needed if trends suggest sufficient storm coverage is likely. DISCUSSION...Elevated thunderstorms continue across far southeast NM and the TX South Plains amid persistent warm-air advection to the north of a surface low centered over the Pecos County TX vicinity. Large hail will remain possible with these storms over the next hour or two. Farther south, a recent attempt at deep convection near the center of the low over Crane, Midland, and Upton Counties in TX failed, but additional attempts are expected in this area as surface convergence persists and large-scale forcing for ascent gradually increases. Steep mid-level lapse rates and robust deep-layer vertical shear across this region would support strong updrafts capable of large to very large hail with any sustained development. Primary uncertainty is whether or not updrafts can be sustained amid the substantial low/mid-level dry air in place. Given the conditional risk for large to very large hail and potential need for a watch, observational data and convective trends will be monitored closely over the next couple of hours for signs that deeper convection can be maintained. ..Mosier/Smith.. 04/09/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SJT...LUB...MAF... LAT...LON 32900372 33200238 32290045 31150010 30700107 31330298 32900372 Read more

MD 0392 CONCERNING SEVERE THUNDERSTORM WATCH 93... FOR NORTH-CENTRAL INTO NORTHEAST TX
Mesoscale Discussion 0392 NWS Storm Prediction Center Norman OK 0257 AM CDT Tue Apr 09 2024 Areas affected...North-Central into Northeast TX Concerning...Severe Thunderstorm Watch 93... Valid 090757Z - 090930Z The severe weather threat for Severe Thunderstorm Watch 93 continues. SUMMARY...Isolated damaging gusts will remain possible for the next few hours from north-central Texas into northeast Texas. DISCUSSION...Recent surface analysis places a meso-low coincident with the ongoing thunderstorm over northeast portions of the Metroplex. An outflow-augmented cold front extends southwestward from this low into southwest TX. A warm front also extends eastward from this low into northeast TX. Airmass to the east of the ongoing thunderstorm is characterized by low-level stability beneath steep mid-level lapse rates and moderate deep-layer vertical shear. This environment supports the persistence of the ongoing storms as they continue eastward, likely trending more elevated with time. Even so, occasionally strong to severe downdrafts could still reach the surface over the next hour or two, particularly as this storm interacts with the warm front (as evidenced by a recent gust of 53 kt at KDFW). Farther south and west, the airmass is not as hostile to surface-based storms and additional development along the southeastward-progressing front/outflow is possible. However, the notably dry mid-levels will likely act as a deterrent for sustained updrafts, limiting the likelihood for mature updrafts and keeping the overall severe potential low. ..Mosier.. 04/09/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SHV...FWD... LAT...LON 33129718 33689628 33749568 33329513 32849509 32019733 32009830 32559830 33129718 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Apr 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Severe potential should be low for a few days in the wake of the eastern U.S. trough shifting offshore. Primary feature of concern will be an amplified upper low, initially off the CA coast on D4, that gets kicked east by an upstream wave digging towards the Pacific Northwest through early next week. Air mass modification will ensue northward from the western Gulf by late D4 with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures. 00Z ensemble guidance, especially the ECENS, has largely trended towards yesterday's 00Z deterministic guidance, with most members depicting pronounced lee cyclogenesis around the eastern CO vicinity. Sufficient confidence exists to initiate a severe weather highlight for D7 based on the consensus timing of the shortwave trough ejection over the Southwest. Severe potential will likely persist into D8 with an area-of-interest from the southern Great Plains to the Upper Midwest. Spread is too large within the latest deterministic runs and ensemble members to warrant a 15 percent highlight yet. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near 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 steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024 Read more

MD 0390 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR TX PERMIAN BASIN VICINITY
Mesoscale Discussion 0390 NWS Storm Prediction Center Norman OK 1059 PM CDT Mon Apr 08 2024 Areas affected...TX Permian Basin vicinity Concerning...Severe potential...Watch possible Valid 090359Z - 090630Z Probability of Watch Issuance...60 percent SUMMARY...Severe thunderstorm development will be possible overnight, with a threat of large hail. DISCUSSION...Low-level moisture continues to stream northwestward late this evening into portions of the TX Permian Basin region. Meanwhile, WV and IR imagery suggests that ascent related to the deep upper-level trough over the Southwest is beginning to overspread the region. While timing remains uncertain, storm development will become increasingly likely overnight, especially near/north of a southward-moving cold front. Steep midlevel lapse rates, MUCAPE increasing into the 1000-2000 J/kg range, and effective shear of 40+ kts will support elevated supercell potential, with an attendant threat of large hail in the 1.5 - 2 inch diameter range. Severe-storm coverage remains somewhat uncertain overnight and could remain rather isolated, but eventual watch issuance is possible given the potential for elevated supercells. ..Dean/Hart.. 04/09/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SJT...LUB...MAF... LAT...LON 32360300 32700297 33040291 33200177 33110124 32510060 31860073 31130112 30860168 30770276 31710295 32360300 Read more