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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 AM CDT Mon Mar 18 2024 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON ACROSS CENTRAL FL AND MUCH OF THE FL ATLANTIC COAST... ...SUMMARY... Isolated large hail and wind damage is possible this afternoon across central Florida and along much of the Florida Atlantic coast. ...FL this afternoon... A northern stream shortwave trough will dig from the mid MS Valley this morning to the southern Appalachians this evening and off the Atlantic coast by early Tuesday. An associated stalled surface front across north FL this morning will begin to accelerate southeastward across the peninsula this evening through early Tuesday. The more pronounced midlevel height falls and forcing for ascent will pass north of FL, leaving shallow ascent along the front and/or differential heating boundaries (from convection moving inland from the northeast Gulf of Mexico this morning) to focus thunderstorm development. Forecast soundings suggest that moderate buoyancy (MLCAPE near 1500 J/kg), steep low-level lapse rates and 50 kt midlevel flow with relatively straight hodographs could support a supercell capable of producing isolated large hail (1-1.75 inches in diameter) and damaging gusts near 60 mph. The severe threat will peak by early-mid afternoon and then diminish into this evening. ...AZ/southern CA through this evening... As part of a Rex block, a closed low over AZ will drift westward today as an embedded speed max pivots from northern AZ toward southern CA. Low-level moisture will remain modest, but cool midlevel temperatures and daytime heating will contribute to at least weak buoyancy (SBCAPE of 250-750 J/kg). A few clusters of storms will form in the main band of ascent over the rim this afternoon, while other storms are expected to spread southwestward off the higher terrain toward the southern CA coast. The threat for severe storms will remain quite low, but the strongest storms could produce gusty outflow winds and small hail. ..Thompson/Dean.. 03/18/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 AM CDT Mon Mar 18 2024 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON ACROSS CENTRAL FL AND MUCH OF THE FL ATLANTIC COAST... ...SUMMARY... Isolated large hail and wind damage is possible this afternoon across central Florida and along much of the Florida Atlantic coast. ...FL this afternoon... A northern stream shortwave trough will dig from the mid MS Valley this morning to the southern Appalachians this evening and off the Atlantic coast by early Tuesday. An associated stalled surface front across north FL this morning will begin to accelerate southeastward across the peninsula this evening through early Tuesday. The more pronounced midlevel height falls and forcing for ascent will pass north of FL, leaving shallow ascent along the front and/or differential heating boundaries (from convection moving inland from the northeast Gulf of Mexico this morning) to focus thunderstorm development. Forecast soundings suggest that moderate buoyancy (MLCAPE near 1500 J/kg), steep low-level lapse rates and 50 kt midlevel flow with relatively straight hodographs could support a supercell capable of producing isolated large hail (1-1.75 inches in diameter) and damaging gusts near 60 mph. The severe threat will peak by early-mid afternoon and then diminish into this evening. ...AZ/southern CA through this evening... As part of a Rex block, a closed low over AZ will drift westward today as an embedded speed max pivots from northern AZ toward southern CA. Low-level moisture will remain modest, but cool midlevel temperatures and daytime heating will contribute to at least weak buoyancy (SBCAPE of 250-750 J/kg). A few clusters of storms will form in the main band of ascent over the rim this afternoon, while other storms are expected to spread southwestward off the higher terrain toward the southern CA coast. The threat for severe storms will remain quite low, but the strongest storms could produce gusty outflow winds and small hail. ..Thompson/Dean.. 03/18/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 AM CDT Mon Mar 18 2024 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON ACROSS CENTRAL FL AND MUCH OF THE FL ATLANTIC COAST... ...SUMMARY... Isolated large hail and wind damage is possible this afternoon across central Florida and along much of the Florida Atlantic coast. ...FL this afternoon... A northern stream shortwave trough will dig from the mid MS Valley this morning to the southern Appalachians this evening and off the Atlantic coast by early Tuesday. An associated stalled surface front across north FL this morning will begin to accelerate southeastward across the peninsula this evening through early Tuesday. The more pronounced midlevel height falls and forcing for ascent will pass north of FL, leaving shallow ascent along the front and/or differential heating boundaries (from convection moving inland from the northeast Gulf of Mexico this morning) to focus thunderstorm development. Forecast soundings suggest that moderate buoyancy (MLCAPE near 1500 J/kg), steep low-level lapse rates and 50 kt midlevel flow with relatively straight hodographs could support a supercell capable of producing isolated large hail (1-1.75 inches in diameter) and damaging gusts near 60 mph. The severe threat will peak by early-mid afternoon and then diminish into this evening. ...AZ/southern CA through this evening... As part of a Rex block, a closed low over AZ will drift westward today as an embedded speed max pivots from northern AZ toward southern CA. Low-level moisture will remain modest, but cool midlevel temperatures and daytime heating will contribute to at least weak buoyancy (SBCAPE of 250-750 J/kg). A few clusters of storms will form in the main band of ascent over the rim this afternoon, while other storms are expected to spread southwestward off the higher terrain toward the southern CA coast. The threat for severe storms will remain quite low, but the strongest storms could produce gusty outflow winds and small hail. ..Thompson/Dean.. 03/18/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Mon Mar 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range models suggest that a blocking pattern evolving across the northeastern Pacific may be relatively short-lived, with flow across the central into eastern mid-latitude Pacific becoming more progressive. As a high initially centered near or southwest of the Gulf of Alaska breaks down, it appears that troughing within a couple of initial streams to its east will come in phase and contribute to amplifying larger-scale troughing developing inland of the Pacific coast early next weekend, then into the Great Plains by early next week. Embedded short waves progressing through this regime could provide support for significant surface cyclogenesis to the lee of the Rockies, particularly by next Sunday into Monday. There appears a general consensus among latest guidance that a developing cyclone across the Texas/Oklahoma Panhandle vicinity, trailing dryline southward into northwest Texas, and surface front extending east-northeastward across Kansas into the lower Missouri Valley could provide focus for organized severe thunderstorm development Sunday afternoon into Sunday night. The cyclone may then migrate northeastward along the front across the lower Missouri Valley into the Upper Midwest Monday through Monday night, accompanied by a potentially more widespread severe weather threat across the southeastern Great Plains and lower/middle Mississippi Valleys. However, potential also exists for this to be considerably modulated by cold air, initially banked up against the northern U.S. and Canadian Rockies into much of the upper Mississippi Valley, which may tend to nose further southward through the high plains prior to the emergence of the primary short wave trough. Furthermore, in the wake of an amplifying mid-level trough and associated cyclogenesis still forecast offshore of the southern Atlantic Seaboard, low-level moistening on southerly return flow off the Gulf of Mexico may not be optimal. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Mon Mar 18 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE TEXAS PANHANDLE AND ADJACENT WESTERN OKLAHOMA...AND WEDNESDAY NIGHT ACROSS THE TEXAS HILL COUNTRY VICINITY... ...SUMMARY... A couple clusters of thunderstorm activity may develop across the southern Great Plains late Wednesday afternoon into Wednesday night. Some of these storms could be accompanied by a risk for severe hail and gusty winds. ...Synopsis... As a significant short wave impulse, emerging from the base of larger-scale mid-level troughing centered near the Atlantic Seaboard, accelerates into the northern Atlantic, models continue to indicate that a less amplified split flow will gradually evolve east of the Rockies through the western Atlantic. Another vigorous short wave trough is forecast to continue digging within one branch, east-southeast of the Upper Midwest and Great Lakes region through much of the Northeast by the end of the period. It appears that the leading edge of an associated reinforcing low-level cold intrusion may advance through the southern Mid Atlantic coast vicinity and Tennessee Valley by 12Z Thursday, while advancing more slowly southward through the Ozark Plateau and central Great Plains. In another branch, a low amplitude wave emerging from the Southwest is forecast to progress into a lingering (but more weakly) confluent regime to the lee of the southern Rockies. It appears that surface troughing across the southern Great Plains will remain weak, with little in the way of substantive surface cyclogenesis. But an area of lower pressure may form in association with a remnant cyclonic vorticity center progressing into the Texas Panhandle vicinity by late Wednesday afternoon. In the wake of a prior intrusion of cool/dry air through much of the Gulf Basin, guidance continues to indicate that low-level moisture return off a modifying Gulf boundary layer will be limited, with better boundary-layer moisture not reaching the lower Rio Grande Valley/Texas coast until Wednesday night. ...Texas Panhandle vicinity... There is considerable spread concerning the evolution and progression of the approaching mid-level perturbation and the possible weak surface low development. But guidance generally suggests that forcing for ascent near/east of the low may ultimately support a developing cluster of thunderstorms by Wednesday evening. Preceding this development, surface dew points near the low may not increase much beyond 50 F. But, with daytime heating, a well-mixed boundary layer may become modestly deep, with CAPE increasing to around 500 J/kg, and perhaps locally up to 1000 J/kg, beneath relatively cold mid-level air including 500 mb temperatures around -20 to -22 C. Although lower/mid-tropospheric wind fields and deep-layer shear are forecast to become modest, at best, the environment may become supportive of strong initial convection which may pose a risk for marginally severe hail and wind. ...Central/Southern Texas... Beneath stronger southwesterly mid-level flow, more supportive of potential for organized severe convection, warm elevated mixed-layer air (based near or just above 850 mb) appears likely to strongly inhibit vigorous convective development, at least into Wednesday evening. Thereafter, mid/upper forcing for ascent and cooling with the approaching trough may sufficiently erode the inhibition to support thunderstorm initiation, with guidance generally suggesting highest probabilities across the Hill Country vicinity. Based on NAM forecast soundings, among other output, boundary-layer moisture may not be sufficient to support more than weak CAPE. But some severe hail in stronger storms may not be entirely out of the question, before convection becomes more widespread. ..Kerr.. 03/18/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0131 AM CDT Mon Mar 18 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern through the day on Tuesday is expected to be characterized a large trough across the central and eastern US with a decaying cutoff low across the southwestern US. At the surface, this would result in a ridge near the Gulf Coast. Although winds across the northern and central Florida peninsula are currently forecast to be light, relative humidity may be in the 30-40% range. This may result in pockets of elevated fire conditions across this region. However, given the moist fuels and the uncertainty on wind speeds, will not introduce Elevated highlights for now. Elsewhere across the continental US, higher relative humidity is expected to generally keep fire concerns minimal. ..Supinie.. 03/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0131 AM CDT Mon Mar 18 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern through the day on Tuesday is expected to be characterized a large trough across the central and eastern US with a decaying cutoff low across the southwestern US. At the surface, this would result in a ridge near the Gulf Coast. Although winds across the northern and central Florida peninsula are currently forecast to be light, relative humidity may be in the 30-40% range. This may result in pockets of elevated fire conditions across this region. However, given the moist fuels and the uncertainty on wind speeds, will not introduce Elevated highlights for now. Elsewhere across the continental US, higher relative humidity is expected to generally keep fire concerns minimal. ..Supinie.. 03/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0131 AM CDT Mon Mar 18 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern through the day on Tuesday is expected to be characterized a large trough across the central and eastern US with a decaying cutoff low across the southwestern US. At the surface, this would result in a ridge near the Gulf Coast. Although winds across the northern and central Florida peninsula are currently forecast to be light, relative humidity may be in the 30-40% range. This may result in pockets of elevated fire conditions across this region. However, given the moist fuels and the uncertainty on wind speeds, will not introduce Elevated highlights for now. Elsewhere across the continental US, higher relative humidity is expected to generally keep fire concerns minimal. ..Supinie.. 03/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0131 AM CDT Mon Mar 18 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... The mid-level pattern through the day on Tuesday is expected to be characterized a large trough across the central and eastern US with a decaying cutoff low across the southwestern US. At the surface, this would result in a ridge near the Gulf Coast. Although winds across the northern and central Florida peninsula are currently forecast to be light, relative humidity may be in the 30-40% range. This may result in pockets of elevated fire conditions across this region. However, given the moist fuels and the uncertainty on wind speeds, will not introduce Elevated highlights for now. Elsewhere across the continental US, higher relative humidity is expected to generally keep fire concerns minimal. ..Supinie.. 03/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more