SPC Mar 6, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Wed Mar 06 2024 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF PENINSULAR FLORIDA...SOUTH CAROLINA AND PARTS OF WEST-CENTRAL TO NORTH TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible today over parts of peninsular Florida and South Carolina, and late afternoon into tonight over parts of west-central to north Texas. ...Synopsis... In mid/upper levels, a progressive and amplifying pattern is forecast over the CONUS through the period, mainly related to a well-developed trough now approaching the CA coastline. The accompanying 500-mb low should move over the Point Conception area around 18Z, then weaken inland across southern CA overnight. However, the trough will remain strong as an open-wave feature, as it approaches the lower Colorado River Valley around 12Z. Downstream, a series of minor perturbations embedded in the subtropical/southern stream will traverse northern MX and much of TX. Farther east, a shortwave trough was quite evident in moisture-channel imagery over parts of TN, AL and GA, extending southward to the northeastern Gulf. This initially rather broad perturbation will consolidate somewhat and cross parts of GA and the western/upstate Carolinas by 00Z, then move northeastward into the Mid-Atlantic by the end of the period. At the surface, 11Z analysis showed a series of weak lows and troughs scattered across the Southeast amid weak surface flow, with a warm front along the SC and southern NC coast, then bending southeastward offshore from HSE. Northward movement of this boundary will be delayed by precip/clouds this morning, but should occur this afternoon across the inland Carolinas. Meanwhile, another frontal zone -- initially drawn over deep south TX -- should migrate northward as a warm front today and tonight across much of central/north TX and into OK tonight, connecting to overnight surface cyclogenesis progged for the northwestern TX Panhandle. ...FL... Widely scattered to scattered thunderstorms are expected to develop this afternoon along sea-breeze boundaries and smaller-scale zones of lift, amidst diabatically weakened MLCINH and favorable low-level moisture. The best-organized convection may produce damaging to isolated severe downdrafts and isolated severe hail. The southern fringes of cooling aloft related to the southeastern CONUS perturbation, atop upper 60s to low 70s F surface dewpoints, in a deep troposphere, will lead to peak/preconvective MLCAPE in the 1500-2500 J/kg range. Activity should be predominantly multicellular, with modest low/middle level flow limiting most measures of bulk shear. However, relatively strong upper/anvil- level winds will ventilate convection to some extent and contribute to around 50-70 kt of shear from LCL to EL. Near the East Coast sea breeze, some backed low-level flow is possible that may augment low-level and deep shear enough for at least transient storm-scale rotation and a marginal/brief tornado potential as well. ...SC and vicinity... An extensive plume of precip -- with isolated to widely scattered, sporadic, embedded thunderstorms -- is shifting roughly northeastward across parts of GA, the Carolinas and eastern TN. This activity is supported regionally by a combination of warm advection and moisture transport, with related modest, elevated destabilization. Severe conditions are not expected with this activity due to insufficiency of both buoyancy and shear. However, especially over the Low Country/coastal plain and perhaps central SC, a second round of convective development is expected late this afternoon into evening, offering marginally severe hail or strong/damaging gusts. This activity should follow several hours of airmass recovery through a combination of diabatic heating, continued low-level warm advection, and DCVA/cooling aloft nearer to the "cold-core" region of mid/upper-level perturbation. These processes should steepen low-level lapse rates and weaken MLCINH, while slightly increasing previously poor midlevel lapse rates by late afternoon. In combination with favorable near-surface moisture (dewpoints generally low/mid 60s F), this should support around 800-1200 J/kg MLCAPE. Though low-level hodographs/SRH/bulk shear shouldn't be large, around 30-40 kt effective-shear magnitudes are expected, with some organized multicell or transient supercell structures possible. Convection should weaken and exit the area by late evening. ...West-central/northwest/north-central TX... Isolated to widely scattered thunderstorms are possible from late afternoon into the overnight period -- initially over parts of the Big Country/Concho Valley regions of west-central TX, then spreading/shifting northward and northeastward with time tonight. Isolated severe hail is the main concern, though strong/locally severe gusts cannot be ruled out either. The northward-returning frontal zone appears to be the most probable source of low-level lift, through some chance exists for surface parcels to reach convective temperature on southwestern parts of the outlook area. Low-level warm advection and moisture transport/recovery will strengthen considerably from late afternoon through overnight across the region, as the Pacific mid/upper trough approaches, the subtle southern-stream perturbations move overhead, and southwest flow increases aloft. This should lead to increasing convective coverage, though uncertainty lingers on spatial extent and density, given the subtlety of overall lift. Environmentally, upstream high-cloud cover prevalent in satellite imagery should thicken through the day, lending further uncertainty to specific initiation timing/location, but still allowing enough heating to weaken MLCINH by late afternoon. CINH will weaken further this evening into tonight because of warm advection/ isentropic ascent to LFC -- particularly as the southerly LLJ strengthens overnight to around 40-50 kt. The moisture increase (especially above the surface) and warm advection will contribute to MUCAPE around 1000 J/kg, most of it in low/middle levels below a more-stable mid/upper regime related to the cloud deck. Some convective organization is possible, amidst 30-40 kt effective-shear magnitudes. ..Edwards/Jewell.. 03/06/2024 Read more

SPC Mar 6, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Wed Mar 06 2024 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF PENINSULAR FLORIDA...SOUTH CAROLINA AND PARTS OF WEST-CENTRAL TO NORTH TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible today over parts of peninsular Florida and South Carolina, and late afternoon into tonight over parts of west-central to north Texas. ...Synopsis... In mid/upper levels, a progressive and amplifying pattern is forecast over the CONUS through the period, mainly related to a well-developed trough now approaching the CA coastline. The accompanying 500-mb low should move over the Point Conception area around 18Z, then weaken inland across southern CA overnight. However, the trough will remain strong as an open-wave feature, as it approaches the lower Colorado River Valley around 12Z. Downstream, a series of minor perturbations embedded in the subtropical/southern stream will traverse northern MX and much of TX. Farther east, a shortwave trough was quite evident in moisture-channel imagery over parts of TN, AL and GA, extending southward to the northeastern Gulf. This initially rather broad perturbation will consolidate somewhat and cross parts of GA and the western/upstate Carolinas by 00Z, then move northeastward into the Mid-Atlantic by the end of the period. At the surface, 11Z analysis showed a series of weak lows and troughs scattered across the Southeast amid weak surface flow, with a warm front along the SC and southern NC coast, then bending southeastward offshore from HSE. Northward movement of this boundary will be delayed by precip/clouds this morning, but should occur this afternoon across the inland Carolinas. Meanwhile, another frontal zone -- initially drawn over deep south TX -- should migrate northward as a warm front today and tonight across much of central/north TX and into OK tonight, connecting to overnight surface cyclogenesis progged for the northwestern TX Panhandle. ...FL... Widely scattered to scattered thunderstorms are expected to develop this afternoon along sea-breeze boundaries and smaller-scale zones of lift, amidst diabatically weakened MLCINH and favorable low-level moisture. The best-organized convection may produce damaging to isolated severe downdrafts and isolated severe hail. The southern fringes of cooling aloft related to the southeastern CONUS perturbation, atop upper 60s to low 70s F surface dewpoints, in a deep troposphere, will lead to peak/preconvective MLCAPE in the 1500-2500 J/kg range. Activity should be predominantly multicellular, with modest low/middle level flow limiting most measures of bulk shear. However, relatively strong upper/anvil- level winds will ventilate convection to some extent and contribute to around 50-70 kt of shear from LCL to EL. Near the East Coast sea breeze, some backed low-level flow is possible that may augment low-level and deep shear enough for at least transient storm-scale rotation and a marginal/brief tornado potential as well. ...SC and vicinity... An extensive plume of precip -- with isolated to widely scattered, sporadic, embedded thunderstorms -- is shifting roughly northeastward across parts of GA, the Carolinas and eastern TN. This activity is supported regionally by a combination of warm advection and moisture transport, with related modest, elevated destabilization. Severe conditions are not expected with this activity due to insufficiency of both buoyancy and shear. However, especially over the Low Country/coastal plain and perhaps central SC, a second round of convective development is expected late this afternoon into evening, offering marginally severe hail or strong/damaging gusts. This activity should follow several hours of airmass recovery through a combination of diabatic heating, continued low-level warm advection, and DCVA/cooling aloft nearer to the "cold-core" region of mid/upper-level perturbation. These processes should steepen low-level lapse rates and weaken MLCINH, while slightly increasing previously poor midlevel lapse rates by late afternoon. In combination with favorable near-surface moisture (dewpoints generally low/mid 60s F), this should support around 800-1200 J/kg MLCAPE. Though low-level hodographs/SRH/bulk shear shouldn't be large, around 30-40 kt effective-shear magnitudes are expected, with some organized multicell or transient supercell structures possible. Convection should weaken and exit the area by late evening. ...West-central/northwest/north-central TX... Isolated to widely scattered thunderstorms are possible from late afternoon into the overnight period -- initially over parts of the Big Country/Concho Valley regions of west-central TX, then spreading/shifting northward and northeastward with time tonight. Isolated severe hail is the main concern, though strong/locally severe gusts cannot be ruled out either. The northward-returning frontal zone appears to be the most probable source of low-level lift, through some chance exists for surface parcels to reach convective temperature on southwestern parts of the outlook area. Low-level warm advection and moisture transport/recovery will strengthen considerably from late afternoon through overnight across the region, as the Pacific mid/upper trough approaches, the subtle southern-stream perturbations move overhead, and southwest flow increases aloft. This should lead to increasing convective coverage, though uncertainty lingers on spatial extent and density, given the subtlety of overall lift. Environmentally, upstream high-cloud cover prevalent in satellite imagery should thicken through the day, lending further uncertainty to specific initiation timing/location, but still allowing enough heating to weaken MLCINH by late afternoon. CINH will weaken further this evening into tonight because of warm advection/ isentropic ascent to LFC -- particularly as the southerly LLJ strengthens overnight to around 40-50 kt. The moisture increase (especially above the surface) and warm advection will contribute to MUCAPE around 1000 J/kg, most of it in low/middle levels below a more-stable mid/upper regime related to the cloud deck. Some convective organization is possible, amidst 30-40 kt effective-shear magnitudes. ..Edwards/Jewell.. 03/06/2024 Read more

SPC Mar 6, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Wed Mar 06 2024 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF PENINSULAR FLORIDA...SOUTH CAROLINA AND PARTS OF WEST-CENTRAL TO NORTH TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible today over parts of peninsular Florida and South Carolina, and late afternoon into tonight over parts of west-central to north Texas. ...Synopsis... In mid/upper levels, a progressive and amplifying pattern is forecast over the CONUS through the period, mainly related to a well-developed trough now approaching the CA coastline. The accompanying 500-mb low should move over the Point Conception area around 18Z, then weaken inland across southern CA overnight. However, the trough will remain strong as an open-wave feature, as it approaches the lower Colorado River Valley around 12Z. Downstream, a series of minor perturbations embedded in the subtropical/southern stream will traverse northern MX and much of TX. Farther east, a shortwave trough was quite evident in moisture-channel imagery over parts of TN, AL and GA, extending southward to the northeastern Gulf. This initially rather broad perturbation will consolidate somewhat and cross parts of GA and the western/upstate Carolinas by 00Z, then move northeastward into the Mid-Atlantic by the end of the period. At the surface, 11Z analysis showed a series of weak lows and troughs scattered across the Southeast amid weak surface flow, with a warm front along the SC and southern NC coast, then bending southeastward offshore from HSE. Northward movement of this boundary will be delayed by precip/clouds this morning, but should occur this afternoon across the inland Carolinas. Meanwhile, another frontal zone -- initially drawn over deep south TX -- should migrate northward as a warm front today and tonight across much of central/north TX and into OK tonight, connecting to overnight surface cyclogenesis progged for the northwestern TX Panhandle. ...FL... Widely scattered to scattered thunderstorms are expected to develop this afternoon along sea-breeze boundaries and smaller-scale zones of lift, amidst diabatically weakened MLCINH and favorable low-level moisture. The best-organized convection may produce damaging to isolated severe downdrafts and isolated severe hail. The southern fringes of cooling aloft related to the southeastern CONUS perturbation, atop upper 60s to low 70s F surface dewpoints, in a deep troposphere, will lead to peak/preconvective MLCAPE in the 1500-2500 J/kg range. Activity should be predominantly multicellular, with modest low/middle level flow limiting most measures of bulk shear. However, relatively strong upper/anvil- level winds will ventilate convection to some extent and contribute to around 50-70 kt of shear from LCL to EL. Near the East Coast sea breeze, some backed low-level flow is possible that may augment low-level and deep shear enough for at least transient storm-scale rotation and a marginal/brief tornado potential as well. ...SC and vicinity... An extensive plume of precip -- with isolated to widely scattered, sporadic, embedded thunderstorms -- is shifting roughly northeastward across parts of GA, the Carolinas and eastern TN. This activity is supported regionally by a combination of warm advection and moisture transport, with related modest, elevated destabilization. Severe conditions are not expected with this activity due to insufficiency of both buoyancy and shear. However, especially over the Low Country/coastal plain and perhaps central SC, a second round of convective development is expected late this afternoon into evening, offering marginally severe hail or strong/damaging gusts. This activity should follow several hours of airmass recovery through a combination of diabatic heating, continued low-level warm advection, and DCVA/cooling aloft nearer to the "cold-core" region of mid/upper-level perturbation. These processes should steepen low-level lapse rates and weaken MLCINH, while slightly increasing previously poor midlevel lapse rates by late afternoon. In combination with favorable near-surface moisture (dewpoints generally low/mid 60s F), this should support around 800-1200 J/kg MLCAPE. Though low-level hodographs/SRH/bulk shear shouldn't be large, around 30-40 kt effective-shear magnitudes are expected, with some organized multicell or transient supercell structures possible. Convection should weaken and exit the area by late evening. ...West-central/northwest/north-central TX... Isolated to widely scattered thunderstorms are possible from late afternoon into the overnight period -- initially over parts of the Big Country/Concho Valley regions of west-central TX, then spreading/shifting northward and northeastward with time tonight. Isolated severe hail is the main concern, though strong/locally severe gusts cannot be ruled out either. The northward-returning frontal zone appears to be the most probable source of low-level lift, through some chance exists for surface parcels to reach convective temperature on southwestern parts of the outlook area. Low-level warm advection and moisture transport/recovery will strengthen considerably from late afternoon through overnight across the region, as the Pacific mid/upper trough approaches, the subtle southern-stream perturbations move overhead, and southwest flow increases aloft. This should lead to increasing convective coverage, though uncertainty lingers on spatial extent and density, given the subtlety of overall lift. Environmentally, upstream high-cloud cover prevalent in satellite imagery should thicken through the day, lending further uncertainty to specific initiation timing/location, but still allowing enough heating to weaken MLCINH by late afternoon. CINH will weaken further this evening into tonight because of warm advection/ isentropic ascent to LFC -- particularly as the southerly LLJ strengthens overnight to around 40-50 kt. The moisture increase (especially above the surface) and warm advection will contribute to MUCAPE around 1000 J/kg, most of it in low/middle levels below a more-stable mid/upper regime related to the cloud deck. Some convective organization is possible, amidst 30-40 kt effective-shear magnitudes. ..Edwards/Jewell.. 03/06/2024 Read more

SPC Mar 6, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Wed Mar 06 2024 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF PENINSULAR FLORIDA...SOUTH CAROLINA AND PARTS OF WEST-CENTRAL TO NORTH TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible today over parts of peninsular Florida and South Carolina, and late afternoon into tonight over parts of west-central to north Texas. ...Synopsis... In mid/upper levels, a progressive and amplifying pattern is forecast over the CONUS through the period, mainly related to a well-developed trough now approaching the CA coastline. The accompanying 500-mb low should move over the Point Conception area around 18Z, then weaken inland across southern CA overnight. However, the trough will remain strong as an open-wave feature, as it approaches the lower Colorado River Valley around 12Z. Downstream, a series of minor perturbations embedded in the subtropical/southern stream will traverse northern MX and much of TX. Farther east, a shortwave trough was quite evident in moisture-channel imagery over parts of TN, AL and GA, extending southward to the northeastern Gulf. This initially rather broad perturbation will consolidate somewhat and cross parts of GA and the western/upstate Carolinas by 00Z, then move northeastward into the Mid-Atlantic by the end of the period. At the surface, 11Z analysis showed a series of weak lows and troughs scattered across the Southeast amid weak surface flow, with a warm front along the SC and southern NC coast, then bending southeastward offshore from HSE. Northward movement of this boundary will be delayed by precip/clouds this morning, but should occur this afternoon across the inland Carolinas. Meanwhile, another frontal zone -- initially drawn over deep south TX -- should migrate northward as a warm front today and tonight across much of central/north TX and into OK tonight, connecting to overnight surface cyclogenesis progged for the northwestern TX Panhandle. ...FL... Widely scattered to scattered thunderstorms are expected to develop this afternoon along sea-breeze boundaries and smaller-scale zones of lift, amidst diabatically weakened MLCINH and favorable low-level moisture. The best-organized convection may produce damaging to isolated severe downdrafts and isolated severe hail. The southern fringes of cooling aloft related to the southeastern CONUS perturbation, atop upper 60s to low 70s F surface dewpoints, in a deep troposphere, will lead to peak/preconvective MLCAPE in the 1500-2500 J/kg range. Activity should be predominantly multicellular, with modest low/middle level flow limiting most measures of bulk shear. However, relatively strong upper/anvil- level winds will ventilate convection to some extent and contribute to around 50-70 kt of shear from LCL to EL. Near the East Coast sea breeze, some backed low-level flow is possible that may augment low-level and deep shear enough for at least transient storm-scale rotation and a marginal/brief tornado potential as well. ...SC and vicinity... An extensive plume of precip -- with isolated to widely scattered, sporadic, embedded thunderstorms -- is shifting roughly northeastward across parts of GA, the Carolinas and eastern TN. This activity is supported regionally by a combination of warm advection and moisture transport, with related modest, elevated destabilization. Severe conditions are not expected with this activity due to insufficiency of both buoyancy and shear. However, especially over the Low Country/coastal plain and perhaps central SC, a second round of convective development is expected late this afternoon into evening, offering marginally severe hail or strong/damaging gusts. This activity should follow several hours of airmass recovery through a combination of diabatic heating, continued low-level warm advection, and DCVA/cooling aloft nearer to the "cold-core" region of mid/upper-level perturbation. These processes should steepen low-level lapse rates and weaken MLCINH, while slightly increasing previously poor midlevel lapse rates by late afternoon. In combination with favorable near-surface moisture (dewpoints generally low/mid 60s F), this should support around 800-1200 J/kg MLCAPE. Though low-level hodographs/SRH/bulk shear shouldn't be large, around 30-40 kt effective-shear magnitudes are expected, with some organized multicell or transient supercell structures possible. Convection should weaken and exit the area by late evening. ...West-central/northwest/north-central TX... Isolated to widely scattered thunderstorms are possible from late afternoon into the overnight period -- initially over parts of the Big Country/Concho Valley regions of west-central TX, then spreading/shifting northward and northeastward with time tonight. Isolated severe hail is the main concern, though strong/locally severe gusts cannot be ruled out either. The northward-returning frontal zone appears to be the most probable source of low-level lift, through some chance exists for surface parcels to reach convective temperature on southwestern parts of the outlook area. Low-level warm advection and moisture transport/recovery will strengthen considerably from late afternoon through overnight across the region, as the Pacific mid/upper trough approaches, the subtle southern-stream perturbations move overhead, and southwest flow increases aloft. This should lead to increasing convective coverage, though uncertainty lingers on spatial extent and density, given the subtlety of overall lift. Environmentally, upstream high-cloud cover prevalent in satellite imagery should thicken through the day, lending further uncertainty to specific initiation timing/location, but still allowing enough heating to weaken MLCINH by late afternoon. CINH will weaken further this evening into tonight because of warm advection/ isentropic ascent to LFC -- particularly as the southerly LLJ strengthens overnight to around 40-50 kt. The moisture increase (especially above the surface) and warm advection will contribute to MUCAPE around 1000 J/kg, most of it in low/middle levels below a more-stable mid/upper regime related to the cloud deck. Some convective organization is possible, amidst 30-40 kt effective-shear magnitudes. ..Edwards/Jewell.. 03/06/2024 Read more

SPC Mar 6, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Wed Mar 06 2024 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF PENINSULAR FLORIDA...SOUTH CAROLINA AND PARTS OF WEST-CENTRAL TO NORTH TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible today over parts of peninsular Florida and South Carolina, and late afternoon into tonight over parts of west-central to north Texas. ...Synopsis... In mid/upper levels, a progressive and amplifying pattern is forecast over the CONUS through the period, mainly related to a well-developed trough now approaching the CA coastline. The accompanying 500-mb low should move over the Point Conception area around 18Z, then weaken inland across southern CA overnight. However, the trough will remain strong as an open-wave feature, as it approaches the lower Colorado River Valley around 12Z. Downstream, a series of minor perturbations embedded in the subtropical/southern stream will traverse northern MX and much of TX. Farther east, a shortwave trough was quite evident in moisture-channel imagery over parts of TN, AL and GA, extending southward to the northeastern Gulf. This initially rather broad perturbation will consolidate somewhat and cross parts of GA and the western/upstate Carolinas by 00Z, then move northeastward into the Mid-Atlantic by the end of the period. At the surface, 11Z analysis showed a series of weak lows and troughs scattered across the Southeast amid weak surface flow, with a warm front along the SC and southern NC coast, then bending southeastward offshore from HSE. Northward movement of this boundary will be delayed by precip/clouds this morning, but should occur this afternoon across the inland Carolinas. Meanwhile, another frontal zone -- initially drawn over deep south TX -- should migrate northward as a warm front today and tonight across much of central/north TX and into OK tonight, connecting to overnight surface cyclogenesis progged for the northwestern TX Panhandle. ...FL... Widely scattered to scattered thunderstorms are expected to develop this afternoon along sea-breeze boundaries and smaller-scale zones of lift, amidst diabatically weakened MLCINH and favorable low-level moisture. The best-organized convection may produce damaging to isolated severe downdrafts and isolated severe hail. The southern fringes of cooling aloft related to the southeastern CONUS perturbation, atop upper 60s to low 70s F surface dewpoints, in a deep troposphere, will lead to peak/preconvective MLCAPE in the 1500-2500 J/kg range. Activity should be predominantly multicellular, with modest low/middle level flow limiting most measures of bulk shear. However, relatively strong upper/anvil- level winds will ventilate convection to some extent and contribute to around 50-70 kt of shear from LCL to EL. Near the East Coast sea breeze, some backed low-level flow is possible that may augment low-level and deep shear enough for at least transient storm-scale rotation and a marginal/brief tornado potential as well. ...SC and vicinity... An extensive plume of precip -- with isolated to widely scattered, sporadic, embedded thunderstorms -- is shifting roughly northeastward across parts of GA, the Carolinas and eastern TN. This activity is supported regionally by a combination of warm advection and moisture transport, with related modest, elevated destabilization. Severe conditions are not expected with this activity due to insufficiency of both buoyancy and shear. However, especially over the Low Country/coastal plain and perhaps central SC, a second round of convective development is expected late this afternoon into evening, offering marginally severe hail or strong/damaging gusts. This activity should follow several hours of airmass recovery through a combination of diabatic heating, continued low-level warm advection, and DCVA/cooling aloft nearer to the "cold-core" region of mid/upper-level perturbation. These processes should steepen low-level lapse rates and weaken MLCINH, while slightly increasing previously poor midlevel lapse rates by late afternoon. In combination with favorable near-surface moisture (dewpoints generally low/mid 60s F), this should support around 800-1200 J/kg MLCAPE. Though low-level hodographs/SRH/bulk shear shouldn't be large, around 30-40 kt effective-shear magnitudes are expected, with some organized multicell or transient supercell structures possible. Convection should weaken and exit the area by late evening. ...West-central/northwest/north-central TX... Isolated to widely scattered thunderstorms are possible from late afternoon into the overnight period -- initially over parts of the Big Country/Concho Valley regions of west-central TX, then spreading/shifting northward and northeastward with time tonight. Isolated severe hail is the main concern, though strong/locally severe gusts cannot be ruled out either. The northward-returning frontal zone appears to be the most probable source of low-level lift, through some chance exists for surface parcels to reach convective temperature on southwestern parts of the outlook area. Low-level warm advection and moisture transport/recovery will strengthen considerably from late afternoon through overnight across the region, as the Pacific mid/upper trough approaches, the subtle southern-stream perturbations move overhead, and southwest flow increases aloft. This should lead to increasing convective coverage, though uncertainty lingers on spatial extent and density, given the subtlety of overall lift. Environmentally, upstream high-cloud cover prevalent in satellite imagery should thicken through the day, lending further uncertainty to specific initiation timing/location, but still allowing enough heating to weaken MLCINH by late afternoon. CINH will weaken further this evening into tonight because of warm advection/ isentropic ascent to LFC -- particularly as the southerly LLJ strengthens overnight to around 40-50 kt. The moisture increase (especially above the surface) and warm advection will contribute to MUCAPE around 1000 J/kg, most of it in low/middle levels below a more-stable mid/upper regime related to the cloud deck. Some convective organization is possible, amidst 30-40 kt effective-shear magnitudes. ..Edwards/Jewell.. 03/06/2024 Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

SPC Mar 6, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Wed Mar 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... A severe threat should persist into Day 4/Saturday across parts of the Southeast as a southern and northern-stream upper trough gradually merge and amplify over the eastern CONUS. Latest deterministic and ensemble guidance has increased confidence that mid to upper 60s surface dewpoints will be able to advance inland across parts of north FL and southern/central GA ahead of convection moving eastward from the central Gulf Coast vicinity. This moisture, in concert with filtered daytime heating, should be sufficient to support surface-based thunderstorms through Saturday afternoon. Even though low-level flow should have a tendency to veer and gradually weaken through the day, sufficient low-level shear should remain in place to foster updraft rotation and some risk for tornadoes, especially Saturday morning. Damaging winds will also remain a concern with any linear structures. A 15% severe area has been added across parts of southeastern AL, north FL, and southern/central GA where confidence is greatest that an organized severe-thunderstorm risk will continue Saturday. There is less confidence in sufficient destabilization occurring across SC/NC Saturday afternoon, but model trends will be closely monitored. Once the cold front associated with the upper trough clears the East Coast, severe potential across the CONUS should remain minimal through early next week. An increasing severe threat may exist by the middle of next week across parts of the Plains as low-level moisture returns northward ahead of another upper trough. But, predictability remains low at that extended time frame. Read more

Most of the Lower Colorado River Authority's agricultural customers in Texas left without water again

1 year 4 months ago
Most of the Lower Colorado River Authority’s agricultural customers in Colorado, Wharton and Matagorda counties will not receive water from the Highland Lake system again this year, due to the lakes being depleted by drought. These customers have not received water from the Highland Lakes since 2022. Lakes Buchanan and Travis were about 42% full, holding 845,086 acre-feet. KVUE News (Austin, Texas), March 3, 2024

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Mar 6, 2024 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 4 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CST Wed Mar 06 2024 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE ARKLATEX INTO THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Severe thunderstorms capable of producing tornadoes, large hail, and damaging winds are expected to spread eastward from the ArkLaTex vicinity across the lower Mississippi Valley and parts of the central Gulf Coast States Friday through Friday night. ...East Texas/Oklahoma into the Lower Mississippi Valley and Southeast... A positively tilted upper trough will eject over the southern Plains into the lower MS Valley on Friday. Enhanced west-southwesterly flow associated with a mid/upper-level jet over these regions will aid in strong deep-layer shear that will support organized severe thunderstorms. There are still some differences in model guidance regarding the placement and strength of multiple surface lows attendant to the ejecting upper trough. The primary surface low of interest should develop from the southern OK/north TX border vicinity towards the ArkLaTex through Friday evening. Rich low-level moisture will attempt to stream northward in tandem with a southerly low-level jet. But, the potential for ongoing convection across north/central TX Friday morning, and its subsequent evolution, may complicate/hinder the northward extent of the greater low-level moisture return across the lower MS Valley. Even with this possible complication, it appears likely that sufficient destabilization will occur across the warm sector, in tandem with modest daytime heating, to support surface-based thunderstorms. Strong low-level and deep-layer shear should foster organized updrafts, including the potential for supercells capable of producing tornadoes and large hail from east TX into LA/MS and eventually the central Gulf Coast. Some 00Z guidance (including the GFS/NAM) show a secondary area of large-hail potential closer to the surface low and colder temperatures aloft/steeper mid-level lapse rates across parts of eastern OK into the ArkLaTex. The Slight Risk has been expanded northward to account for this potential. Damaging winds may become an increasing concern with eastward extent across the lower MS Valley/Southeast Friday evening and continuing overnight into early Saturday morning, as thunderstorms should have a tendency to grow into multiple bowing clusters. Low-level shear will also remain strong enough to support a continued, nocturnal tornado threat across these areas. Given continued model differences, the northward extent of greater low-level moisture remains somewhat uncertain. The Slight Risk delineates where confidence is currently highest in surface-based convection with related risk for tornadoes, large hail, and damaging winds. There is some chance that the Slight Risk will need to be expanded northward across parts of AR/MS/AL if models trend towards a deeper surface low and related warm front located farther north. ..Gleason.. 03/06/2024 Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CST Wed Mar 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO AND WEST TEXAS... ...Synopsis... Within the base of an amplifying large-scale trough over the western CONUS, strong deep-layer west-southwesterly flow will overspread the southern Rockies and adjacent Plains. In response, a lee surface cyclone will deepen in the vicinity of the TX/OK Panhandles, while a southward-extending dryline sharpens over West TX. ...Southern High Plains... West of the dryline, strong downslope warming/drying will contribute to a deeply mixed boundary layer, extending up to around 4.5 km AGL across portions of eastern NM and West TX -- despite increasing mid/high-level clouds ahead of the large-scale trough. This will support an expansive area of 12-15 percent minimum RH and temperatures in the lower 70s across the area. At the same time, a tightening pressure gradient along the southern periphery of the lee cyclone, coupled with strong winds through the deepening boundary layer, will favor 20-25 mph sustained west-southwesterly surface winds (with gusts upwards of 35 mph). Given receptive fuels over the southern High Plains (80th+ percentile ERCs), critical fire-weather conditions are expected across parts of eastern NM and West TX. ..Weinman.. 03/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CST Wed Mar 06 2024 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO AND WEST TEXAS... ...Synopsis... Within the base of an amplifying large-scale trough over the western CONUS, strong deep-layer west-southwesterly flow will overspread the southern Rockies and adjacent Plains. In response, a lee surface cyclone will deepen in the vicinity of the TX/OK Panhandles, while a southward-extending dryline sharpens over West TX. ...Southern High Plains... West of the dryline, strong downslope warming/drying will contribute to a deeply mixed boundary layer, extending up to around 4.5 km AGL across portions of eastern NM and West TX -- despite increasing mid/high-level clouds ahead of the large-scale trough. This will support an expansive area of 12-15 percent minimum RH and temperatures in the lower 70s across the area. At the same time, a tightening pressure gradient along the southern periphery of the lee cyclone, coupled with strong winds through the deepening boundary layer, will favor 20-25 mph sustained west-southwesterly surface winds (with gusts upwards of 35 mph). Given receptive fuels over the southern High Plains (80th+ percentile ERCs), critical fire-weather conditions are expected across parts of eastern NM and West TX. ..Weinman.. 03/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more