Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CDT Wed Mar 20 2024 Valid 201700Z - 211200Z The previous forecast remains on track with only minor adjustments made to both Elevated risk areas based on morning observations and latest forecast guidance. Elevated fire weather conditions are already being observed across northern VA with RH values falling below 30%. This region will see the highest potential for transient critical fire weather conditions as RH values fall to 20-25% by late afternoon amid 15-25 mph winds. Elevated conditions are also noted across portions of the lower OH river valley, and may continue into the late morning hours. However, a gradual decrease in wind speeds should limit the overall fire weather potential. Across southwest TX, the 12 UTC EPZ sounding sampled steep lapse rates above 800 mb, which should facilitate downward mixing of 20-25 mph winds as boundary-layer mixing deepens this afternoon. See the previous discussion below for additional details. ..Moore.. 03/20/2024 .PREV DISCUSSION... /ISSUED 0113 AM CDT Wed Mar 20 2024/ ...Synopsis... Separate areas of Elevated fire-weather conditions are anticipated this afternoon and evening in portions of the Southern High Plains and Mid-Atlantic region. ...Southeastern NM and West TX... A shortwave mid-level trough is expected to gradually weaken and phase with the subtropical jet throughout the day today. As a result, modest westerly flow aloft will yield lee cyclogenesis along the NM/TX border and southerly moisture return across the Southern Plains. To the west, downsloping flow will support steadily drying conditions across southeastern NM and West TX with relative humidities dropping to around 15 percent and wind speeds around 15 mph. Steadily drying fuels -- amidst these dry, windy conditions -- are expected to support an Elevated fire-weather threat across the region this afternoon and evening. ...Mid-Atlantic... A belt of strong northwesterly mid-level flow will move through the Mid-Atlantic throughout the day today. This will support deep boundary-layer mixing and dry, windy surface conditions. Current guidance suggests relative humidities could drop to around 25-30 percent with sustained winds around 15 mph. Finer fuels have dried sufficiently to support some fire spread, warranting an Elevated area across the Mid-Atlantic region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CDT Wed Mar 20 2024 Valid 201700Z - 211200Z The previous forecast remains on track with only minor adjustments made to both Elevated risk areas based on morning observations and latest forecast guidance. Elevated fire weather conditions are already being observed across northern VA with RH values falling below 30%. This region will see the highest potential for transient critical fire weather conditions as RH values fall to 20-25% by late afternoon amid 15-25 mph winds. Elevated conditions are also noted across portions of the lower OH river valley, and may continue into the late morning hours. However, a gradual decrease in wind speeds should limit the overall fire weather potential. Across southwest TX, the 12 UTC EPZ sounding sampled steep lapse rates above 800 mb, which should facilitate downward mixing of 20-25 mph winds as boundary-layer mixing deepens this afternoon. See the previous discussion below for additional details. ..Moore.. 03/20/2024 .PREV DISCUSSION... /ISSUED 0113 AM CDT Wed Mar 20 2024/ ...Synopsis... Separate areas of Elevated fire-weather conditions are anticipated this afternoon and evening in portions of the Southern High Plains and Mid-Atlantic region. ...Southeastern NM and West TX... A shortwave mid-level trough is expected to gradually weaken and phase with the subtropical jet throughout the day today. As a result, modest westerly flow aloft will yield lee cyclogenesis along the NM/TX border and southerly moisture return across the Southern Plains. To the west, downsloping flow will support steadily drying conditions across southeastern NM and West TX with relative humidities dropping to around 15 percent and wind speeds around 15 mph. Steadily drying fuels -- amidst these dry, windy conditions -- are expected to support an Elevated fire-weather threat across the region this afternoon and evening. ...Mid-Atlantic... A belt of strong northwesterly mid-level flow will move through the Mid-Atlantic throughout the day today. This will support deep boundary-layer mixing and dry, windy surface conditions. Current guidance suggests relative humidities could drop to around 25-30 percent with sustained winds around 15 mph. Finer fuels have dried sufficiently to support some fire spread, warranting an Elevated area across the Mid-Atlantic region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1035 AM CDT Wed Mar 20 2024 Valid 201700Z - 211200Z The previous forecast remains on track with only minor adjustments made to both Elevated risk areas based on morning observations and latest forecast guidance. Elevated fire weather conditions are already being observed across northern VA with RH values falling below 30%. This region will see the highest potential for transient critical fire weather conditions as RH values fall to 20-25% by late afternoon amid 15-25 mph winds. Elevated conditions are also noted across portions of the lower OH river valley, and may continue into the late morning hours. However, a gradual decrease in wind speeds should limit the overall fire weather potential. Across southwest TX, the 12 UTC EPZ sounding sampled steep lapse rates above 800 mb, which should facilitate downward mixing of 20-25 mph winds as boundary-layer mixing deepens this afternoon. See the previous discussion below for additional details. ..Moore.. 03/20/2024 .PREV DISCUSSION... /ISSUED 0113 AM CDT Wed Mar 20 2024/ ...Synopsis... Separate areas of Elevated fire-weather conditions are anticipated this afternoon and evening in portions of the Southern High Plains and Mid-Atlantic region. ...Southeastern NM and West TX... A shortwave mid-level trough is expected to gradually weaken and phase with the subtropical jet throughout the day today. As a result, modest westerly flow aloft will yield lee cyclogenesis along the NM/TX border and southerly moisture return across the Southern Plains. To the west, downsloping flow will support steadily drying conditions across southeastern NM and West TX with relative humidities dropping to around 15 percent and wind speeds around 15 mph. Steadily drying fuels -- amidst these dry, windy conditions -- are expected to support an Elevated fire-weather threat across the region this afternoon and evening. ...Mid-Atlantic... A belt of strong northwesterly mid-level flow will move through the Mid-Atlantic throughout the day today. This will support deep boundary-layer mixing and dry, windy surface conditions. Current guidance suggests relative humidities could drop to around 25-30 percent with sustained winds around 15 mph. Finer fuels have dried sufficiently to support some fire spread, warranting an Elevated area across the Mid-Atlantic region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Mar 20 2024 Valid 201300Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING ACROSS WESTERN OK/NORTHWEST TX...AND EARLY THURSDAY MORNING NEAR THE TX COAST... ...SUMMARY... Isolated, marginally severe storms will be possible this afternoon/evening across parts of western Oklahoma and northwest Texas. Isolated large hail will be possible early Thursday morning near the Texas coast. ...Western OK/TX Panhandle this afternoon/evening... A midlevel shortwave trough will begin to move eastward from AZ/NM toward west TX by tonight, with associated downstream cyclogenesis occurring today across eastern NM and the TX Panhandle. Low-level moisture return will be limited in the warm sector, with boundary-layer dewpoints ranging from 40-45 F as surface temperatures warm into the 70s this afternoon along a surface trough/front across western OK and the eastern TX Panhandle. Steepening low-midlevel lapse rates and cool midlevel temperatures will support weak buoyancy, and weak ascent along the boundaries could result in a few storms with the potential to produce marginally severe hail and strong outflow gusts. There is also a low probability of a non-mesocyclone tornado with developing updrafts along the slow-moving front in northwest OK later this afternoon, given steep low-level lapse rates/vertical vorticity along the front. ...South central TX to the coastal plain late tonight... Low-level moisture return will occur in earnest by tonight as a maritime tropical air mass spreads northward from the Bay of Campeche (along the prior stalled front) to the TX coast. Near the end of the period, destabilization will become sufficient for elevated thunderstorm development in the warm advection zone atop a diffuse coastal front. MUCAPE could reach 1000-1500 J/kg as moisture increase below midlevel lapse rates of 7.5-8 C/km, in an environment with sufficiently long hodographs (and some low-level curvature) for a conditional supercell/large hail threat mainly 09-12z. ...Southern New England this afternoon... A deepening midlevel trough will move from ON to New England, as an associated cold front moves across New England later today and cyclogenesis occurs tonight near the ME coast. Moisture/buoyancy will be scant at best ahead of the cold front across southern New England, where some shallow/forced convection may occur along the cold front this afternoon. The convection could be associated with a few strong gusts, but the potential for convectively driven severe gusts appears too low to warrant introduction of an outlook area. ..Thompson/Grams.. 03/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Mar 20 2024 Valid 201300Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING ACROSS WESTERN OK/NORTHWEST TX...AND EARLY THURSDAY MORNING NEAR THE TX COAST... ...SUMMARY... Isolated, marginally severe storms will be possible this afternoon/evening across parts of western Oklahoma and northwest Texas. Isolated large hail will be possible early Thursday morning near the Texas coast. ...Western OK/TX Panhandle this afternoon/evening... A midlevel shortwave trough will begin to move eastward from AZ/NM toward west TX by tonight, with associated downstream cyclogenesis occurring today across eastern NM and the TX Panhandle. Low-level moisture return will be limited in the warm sector, with boundary-layer dewpoints ranging from 40-45 F as surface temperatures warm into the 70s this afternoon along a surface trough/front across western OK and the eastern TX Panhandle. Steepening low-midlevel lapse rates and cool midlevel temperatures will support weak buoyancy, and weak ascent along the boundaries could result in a few storms with the potential to produce marginally severe hail and strong outflow gusts. There is also a low probability of a non-mesocyclone tornado with developing updrafts along the slow-moving front in northwest OK later this afternoon, given steep low-level lapse rates/vertical vorticity along the front. ...South central TX to the coastal plain late tonight... Low-level moisture return will occur in earnest by tonight as a maritime tropical air mass spreads northward from the Bay of Campeche (along the prior stalled front) to the TX coast. Near the end of the period, destabilization will become sufficient for elevated thunderstorm development in the warm advection zone atop a diffuse coastal front. MUCAPE could reach 1000-1500 J/kg as moisture increase below midlevel lapse rates of 7.5-8 C/km, in an environment with sufficiently long hodographs (and some low-level curvature) for a conditional supercell/large hail threat mainly 09-12z. ...Southern New England this afternoon... A deepening midlevel trough will move from ON to New England, as an associated cold front moves across New England later today and cyclogenesis occurs tonight near the ME coast. Moisture/buoyancy will be scant at best ahead of the cold front across southern New England, where some shallow/forced convection may occur along the cold front this afternoon. The convection could be associated with a few strong gusts, but the potential for convectively driven severe gusts appears too low to warrant introduction of an outlook area. ..Thompson/Grams.. 03/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Mar 20 2024 Valid 201300Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING ACROSS WESTERN OK/NORTHWEST TX...AND EARLY THURSDAY MORNING NEAR THE TX COAST... ...SUMMARY... Isolated, marginally severe storms will be possible this afternoon/evening across parts of western Oklahoma and northwest Texas. Isolated large hail will be possible early Thursday morning near the Texas coast. ...Western OK/TX Panhandle this afternoon/evening... A midlevel shortwave trough will begin to move eastward from AZ/NM toward west TX by tonight, with associated downstream cyclogenesis occurring today across eastern NM and the TX Panhandle. Low-level moisture return will be limited in the warm sector, with boundary-layer dewpoints ranging from 40-45 F as surface temperatures warm into the 70s this afternoon along a surface trough/front across western OK and the eastern TX Panhandle. Steepening low-midlevel lapse rates and cool midlevel temperatures will support weak buoyancy, and weak ascent along the boundaries could result in a few storms with the potential to produce marginally severe hail and strong outflow gusts. There is also a low probability of a non-mesocyclone tornado with developing updrafts along the slow-moving front in northwest OK later this afternoon, given steep low-level lapse rates/vertical vorticity along the front. ...South central TX to the coastal plain late tonight... Low-level moisture return will occur in earnest by tonight as a maritime tropical air mass spreads northward from the Bay of Campeche (along the prior stalled front) to the TX coast. Near the end of the period, destabilization will become sufficient for elevated thunderstorm development in the warm advection zone atop a diffuse coastal front. MUCAPE could reach 1000-1500 J/kg as moisture increase below midlevel lapse rates of 7.5-8 C/km, in an environment with sufficiently long hodographs (and some low-level curvature) for a conditional supercell/large hail threat mainly 09-12z. ...Southern New England this afternoon... A deepening midlevel trough will move from ON to New England, as an associated cold front moves across New England later today and cyclogenesis occurs tonight near the ME coast. Moisture/buoyancy will be scant at best ahead of the cold front across southern New England, where some shallow/forced convection may occur along the cold front this afternoon. The convection could be associated with a few strong gusts, but the potential for convectively driven severe gusts appears too low to warrant introduction of an outlook area. ..Thompson/Grams.. 03/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Mar 20 2024 Valid 201300Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING ACROSS WESTERN OK/NORTHWEST TX...AND EARLY THURSDAY MORNING NEAR THE TX COAST... ...SUMMARY... Isolated, marginally severe storms will be possible this afternoon/evening across parts of western Oklahoma and northwest Texas. Isolated large hail will be possible early Thursday morning near the Texas coast. ...Western OK/TX Panhandle this afternoon/evening... A midlevel shortwave trough will begin to move eastward from AZ/NM toward west TX by tonight, with associated downstream cyclogenesis occurring today across eastern NM and the TX Panhandle. Low-level moisture return will be limited in the warm sector, with boundary-layer dewpoints ranging from 40-45 F as surface temperatures warm into the 70s this afternoon along a surface trough/front across western OK and the eastern TX Panhandle. Steepening low-midlevel lapse rates and cool midlevel temperatures will support weak buoyancy, and weak ascent along the boundaries could result in a few storms with the potential to produce marginally severe hail and strong outflow gusts. There is also a low probability of a non-mesocyclone tornado with developing updrafts along the slow-moving front in northwest OK later this afternoon, given steep low-level lapse rates/vertical vorticity along the front. ...South central TX to the coastal plain late tonight... Low-level moisture return will occur in earnest by tonight as a maritime tropical air mass spreads northward from the Bay of Campeche (along the prior stalled front) to the TX coast. Near the end of the period, destabilization will become sufficient for elevated thunderstorm development in the warm advection zone atop a diffuse coastal front. MUCAPE could reach 1000-1500 J/kg as moisture increase below midlevel lapse rates of 7.5-8 C/km, in an environment with sufficiently long hodographs (and some low-level curvature) for a conditional supercell/large hail threat mainly 09-12z. ...Southern New England this afternoon... A deepening midlevel trough will move from ON to New England, as an associated cold front moves across New England later today and cyclogenesis occurs tonight near the ME coast. Moisture/buoyancy will be scant at best ahead of the cold front across southern New England, where some shallow/forced convection may occur along the cold front this afternoon. The convection could be associated with a few strong gusts, but the potential for convectively driven severe gusts appears too low to warrant introduction of an outlook area. ..Thompson/Grams.. 03/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Mar 20 2024 Valid 201300Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING ACROSS WESTERN OK/NORTHWEST TX...AND EARLY THURSDAY MORNING NEAR THE TX COAST... ...SUMMARY... Isolated, marginally severe storms will be possible this afternoon/evening across parts of western Oklahoma and northwest Texas. Isolated large hail will be possible early Thursday morning near the Texas coast. ...Western OK/TX Panhandle this afternoon/evening... A midlevel shortwave trough will begin to move eastward from AZ/NM toward west TX by tonight, with associated downstream cyclogenesis occurring today across eastern NM and the TX Panhandle. Low-level moisture return will be limited in the warm sector, with boundary-layer dewpoints ranging from 40-45 F as surface temperatures warm into the 70s this afternoon along a surface trough/front across western OK and the eastern TX Panhandle. Steepening low-midlevel lapse rates and cool midlevel temperatures will support weak buoyancy, and weak ascent along the boundaries could result in a few storms with the potential to produce marginally severe hail and strong outflow gusts. There is also a low probability of a non-mesocyclone tornado with developing updrafts along the slow-moving front in northwest OK later this afternoon, given steep low-level lapse rates/vertical vorticity along the front. ...South central TX to the coastal plain late tonight... Low-level moisture return will occur in earnest by tonight as a maritime tropical air mass spreads northward from the Bay of Campeche (along the prior stalled front) to the TX coast. Near the end of the period, destabilization will become sufficient for elevated thunderstorm development in the warm advection zone atop a diffuse coastal front. MUCAPE could reach 1000-1500 J/kg as moisture increase below midlevel lapse rates of 7.5-8 C/km, in an environment with sufficiently long hodographs (and some low-level curvature) for a conditional supercell/large hail threat mainly 09-12z. ...Southern New England this afternoon... A deepening midlevel trough will move from ON to New England, as an associated cold front moves across New England later today and cyclogenesis occurs tonight near the ME coast. Moisture/buoyancy will be scant at best ahead of the cold front across southern New England, where some shallow/forced convection may occur along the cold front this afternoon. The convection could be associated with a few strong gusts, but the potential for convectively driven severe gusts appears too low to warrant introduction of an outlook area. ..Thompson/Grams.. 03/20/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Wed Mar 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range models suggest that blocking centered over the northeastern Pacific will break down this weekend, as a more progressive regime shifts across the central into eastern mid-latitude Pacific, and gradually inland through much of the U.S. by the middle to latter portion of next week. Initially, flow downstream of the weakening blocking may undergo amplification, including mid-level troughing offshore of the southern Atlantic Seaboard, and larger-scale mid-level troughing progressing inland of the U.S. Pacific coast through the Great Plains and Mississippi Valley through early next week. Within the inland advancing troughing, there appears reasonable agreement between the ECENS/ECMWF, GEFS and GFS model output that a significant lead short wave perturbation will accelerate northeastward out of the Southwest across the southern Rockies late Sunday into Sunday night. As this occurs, a rather deep cyclone is forecast to continue to form to the lee of the Front Range during the day, before migrating southeastward then eastward into the adjacent high plains. Although it still appears that low-level moisture return in the wake of prior low-level drying and cooling across the northern Gulf Basin may still be on the margins for vigorous thunderstorms, the development of steep lower/mid-tropospheric lapse rates may compensate. Coupled with potentially intense wind fields and strong forcing for ascent, organized severe thunderstorm development seems probable late Sunday afternoon into Sunday night. This may include supercells initially, then an evolving narrow squall line. Into the early through middle portion of next week, uncertainties concerning a subsequent short wave emerging from the Southwest increase. However, it appears probable that there will be at least narrow corridors of strong to severe thunderstorm development on following days across the southeastern Great Plains into lower Mississippi Valley and perhaps parts of the Southeast. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Wed Mar 20 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY THROUGH FRIDAY NIGHT NEAR THE NORTHEASTERN GULF COAST AND ACROSS PARTS OF SOUTHERN FLORIDA AND THE FLORIDA KEYS... ...SUMMARY... Strong thunderstorms may impact the northeastern Gulf coastal waters into immediate coast vicinity and the Florida Keys into portions of southern Florida, Friday through Friday night. This may be accompanied by at least some risk for damaging wind gusts and a tornado or two. ...Synopsis... Blocking centered over the northeastern Pacific may generally persist through this period, but models suggest that some weakening may commence as a more progressive regime gradually develops across the central toward eastern mid-latitude Pacific. Models vary concerning the extent of this weakening, and this probably will have at least some impact on developments within the broadly confluent split downstream flow across North America. In general, another cold intrusion is forecast to the lee of the Rockies, as far south as the Texas Panhandle/Red River Valley and Mid South, and as far east as the Ohio Valley/lower Great Lakes by 12Z Saturday. This will occur to the west and south of a mid-level low becoming quasi-stationary near the southwestern shores of Hudson Bay. In lower latitudes, mid-level troughing is generally forecast to slowly progress east of the lower Mississippi Valley/northwestern Gulf coast region Friday, with one increasingly sheared perturbation shifting toward the southern Appalachians and another perhaps more notable perturbation digging into the north central/northeastern Gulf by early Saturday. Models differ concerning these features, and the larger-scale troughing will be preceded by a subtropical perturbation progressing across the Florida peninsula early Friday. And there is substantive spread concerning the further evolution of a broad, modest area of surface low pressure overspreading the eastern Gulf Coast/South Atlantic Coast by the end of the period. ...Southeast... An initially dry/potentially cool low-level environment across much of the eastern Gulf Coast into Florida peninsula will precede considerable convective development expected to be ongoing at 12Z Friday across the north central Gulf coast/lower Mississippi Valley vicinity, and across the central into northeastern Gulf of Mexico. As this activity continues to spread eastward and northeastward with the large-scale forcing for ascent, forecast soundings indicate a tendency for profiles to trend saturated moist adiabatic. However, there is at least some signal within model output that a warm front may advance from the southeastern Gulf of Mexico across the Florida Keys and portions of the southern Florida peninsula, coincident with an organized cluster of thunderstorms which could pose a risk for producing damaging wind gusts and a couple of tornadoes. Thereafter, trailing outflow may provide a focus for continuing thunderstorm development in the presence of strong deep-layer shear. Additional strong to severe thunderstorm development is possible within the warm sector of the developing area of low pressure, across the northeastern/eastern Gulf of Mexico, some of which might impact the coastal waters and immediate coast Friday night. However, the extent of this potential will probably depend on the details of the surface low evolution, which remains unclear at this time. ..Kerr.. 03/20/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Wed Mar 20 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY THROUGH FRIDAY NIGHT NEAR THE NORTHEASTERN GULF COAST AND ACROSS PARTS OF SOUTHERN FLORIDA AND THE FLORIDA KEYS... ...SUMMARY... Strong thunderstorms may impact the northeastern Gulf coastal waters into immediate coast vicinity and the Florida Keys into portions of southern Florida, Friday through Friday night. This may be accompanied by at least some risk for damaging wind gusts and a tornado or two. ...Synopsis... Blocking centered over the northeastern Pacific may generally persist through this period, but models suggest that some weakening may commence as a more progressive regime gradually develops across the central toward eastern mid-latitude Pacific. Models vary concerning the extent of this weakening, and this probably will have at least some impact on developments within the broadly confluent split downstream flow across North America. In general, another cold intrusion is forecast to the lee of the Rockies, as far south as the Texas Panhandle/Red River Valley and Mid South, and as far east as the Ohio Valley/lower Great Lakes by 12Z Saturday. This will occur to the west and south of a mid-level low becoming quasi-stationary near the southwestern shores of Hudson Bay. In lower latitudes, mid-level troughing is generally forecast to slowly progress east of the lower Mississippi Valley/northwestern Gulf coast region Friday, with one increasingly sheared perturbation shifting toward the southern Appalachians and another perhaps more notable perturbation digging into the north central/northeastern Gulf by early Saturday. Models differ concerning these features, and the larger-scale troughing will be preceded by a subtropical perturbation progressing across the Florida peninsula early Friday. And there is substantive spread concerning the further evolution of a broad, modest area of surface low pressure overspreading the eastern Gulf Coast/South Atlantic Coast by the end of the period. ...Southeast... An initially dry/potentially cool low-level environment across much of the eastern Gulf Coast into Florida peninsula will precede considerable convective development expected to be ongoing at 12Z Friday across the north central Gulf coast/lower Mississippi Valley vicinity, and across the central into northeastern Gulf of Mexico. As this activity continues to spread eastward and northeastward with the large-scale forcing for ascent, forecast soundings indicate a tendency for profiles to trend saturated moist adiabatic. However, there is at least some signal within model output that a warm front may advance from the southeastern Gulf of Mexico across the Florida Keys and portions of the southern Florida peninsula, coincident with an organized cluster of thunderstorms which could pose a risk for producing damaging wind gusts and a couple of tornadoes. Thereafter, trailing outflow may provide a focus for continuing thunderstorm development in the presence of strong deep-layer shear. Additional strong to severe thunderstorm development is possible within the warm sector of the developing area of low pressure, across the northeastern/eastern Gulf of Mexico, some of which might impact the coastal waters and immediate coast Friday night. However, the extent of this potential will probably depend on the details of the surface low evolution, which remains unclear at this time. ..Kerr.. 03/20/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Wed Mar 20 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY THROUGH FRIDAY NIGHT NEAR THE NORTHEASTERN GULF COAST AND ACROSS PARTS OF SOUTHERN FLORIDA AND THE FLORIDA KEYS... ...SUMMARY... Strong thunderstorms may impact the northeastern Gulf coastal waters into immediate coast vicinity and the Florida Keys into portions of southern Florida, Friday through Friday night. This may be accompanied by at least some risk for damaging wind gusts and a tornado or two. ...Synopsis... Blocking centered over the northeastern Pacific may generally persist through this period, but models suggest that some weakening may commence as a more progressive regime gradually develops across the central toward eastern mid-latitude Pacific. Models vary concerning the extent of this weakening, and this probably will have at least some impact on developments within the broadly confluent split downstream flow across North America. In general, another cold intrusion is forecast to the lee of the Rockies, as far south as the Texas Panhandle/Red River Valley and Mid South, and as far east as the Ohio Valley/lower Great Lakes by 12Z Saturday. This will occur to the west and south of a mid-level low becoming quasi-stationary near the southwestern shores of Hudson Bay. In lower latitudes, mid-level troughing is generally forecast to slowly progress east of the lower Mississippi Valley/northwestern Gulf coast region Friday, with one increasingly sheared perturbation shifting toward the southern Appalachians and another perhaps more notable perturbation digging into the north central/northeastern Gulf by early Saturday. Models differ concerning these features, and the larger-scale troughing will be preceded by a subtropical perturbation progressing across the Florida peninsula early Friday. And there is substantive spread concerning the further evolution of a broad, modest area of surface low pressure overspreading the eastern Gulf Coast/South Atlantic Coast by the end of the period. ...Southeast... An initially dry/potentially cool low-level environment across much of the eastern Gulf Coast into Florida peninsula will precede considerable convective development expected to be ongoing at 12Z Friday across the north central Gulf coast/lower Mississippi Valley vicinity, and across the central into northeastern Gulf of Mexico. As this activity continues to spread eastward and northeastward with the large-scale forcing for ascent, forecast soundings indicate a tendency for profiles to trend saturated moist adiabatic. However, there is at least some signal within model output that a warm front may advance from the southeastern Gulf of Mexico across the Florida Keys and portions of the southern Florida peninsula, coincident with an organized cluster of thunderstorms which could pose a risk for producing damaging wind gusts and a couple of tornadoes. Thereafter, trailing outflow may provide a focus for continuing thunderstorm development in the presence of strong deep-layer shear. Additional strong to severe thunderstorm development is possible within the warm sector of the developing area of low pressure, across the northeastern/eastern Gulf of Mexico, some of which might impact the coastal waters and immediate coast Friday night. However, the extent of this potential will probably depend on the details of the surface low evolution, which remains unclear at this time. ..Kerr.. 03/20/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Wed Mar 20 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY THROUGH FRIDAY NIGHT NEAR THE NORTHEASTERN GULF COAST AND ACROSS PARTS OF SOUTHERN FLORIDA AND THE FLORIDA KEYS... ...SUMMARY... Strong thunderstorms may impact the northeastern Gulf coastal waters into immediate coast vicinity and the Florida Keys into portions of southern Florida, Friday through Friday night. This may be accompanied by at least some risk for damaging wind gusts and a tornado or two. ...Synopsis... Blocking centered over the northeastern Pacific may generally persist through this period, but models suggest that some weakening may commence as a more progressive regime gradually develops across the central toward eastern mid-latitude Pacific. Models vary concerning the extent of this weakening, and this probably will have at least some impact on developments within the broadly confluent split downstream flow across North America. In general, another cold intrusion is forecast to the lee of the Rockies, as far south as the Texas Panhandle/Red River Valley and Mid South, and as far east as the Ohio Valley/lower Great Lakes by 12Z Saturday. This will occur to the west and south of a mid-level low becoming quasi-stationary near the southwestern shores of Hudson Bay. In lower latitudes, mid-level troughing is generally forecast to slowly progress east of the lower Mississippi Valley/northwestern Gulf coast region Friday, with one increasingly sheared perturbation shifting toward the southern Appalachians and another perhaps more notable perturbation digging into the north central/northeastern Gulf by early Saturday. Models differ concerning these features, and the larger-scale troughing will be preceded by a subtropical perturbation progressing across the Florida peninsula early Friday. And there is substantive spread concerning the further evolution of a broad, modest area of surface low pressure overspreading the eastern Gulf Coast/South Atlantic Coast by the end of the period. ...Southeast... An initially dry/potentially cool low-level environment across much of the eastern Gulf Coast into Florida peninsula will precede considerable convective development expected to be ongoing at 12Z Friday across the north central Gulf coast/lower Mississippi Valley vicinity, and across the central into northeastern Gulf of Mexico. As this activity continues to spread eastward and northeastward with the large-scale forcing for ascent, forecast soundings indicate a tendency for profiles to trend saturated moist adiabatic. However, there is at least some signal within model output that a warm front may advance from the southeastern Gulf of Mexico across the Florida Keys and portions of the southern Florida peninsula, coincident with an organized cluster of thunderstorms which could pose a risk for producing damaging wind gusts and a couple of tornadoes. Thereafter, trailing outflow may provide a focus for continuing thunderstorm development in the presence of strong deep-layer shear. Additional strong to severe thunderstorm development is possible within the warm sector of the developing area of low pressure, across the northeastern/eastern Gulf of Mexico, some of which might impact the coastal waters and immediate coast Friday night. However, the extent of this potential will probably depend on the details of the surface low evolution, which remains unclear at this time. ..Kerr.. 03/20/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Wed Mar 20 2024 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY THROUGH FRIDAY NIGHT NEAR THE NORTHEASTERN GULF COAST AND ACROSS PARTS OF SOUTHERN FLORIDA AND THE FLORIDA KEYS... ...SUMMARY... Strong thunderstorms may impact the northeastern Gulf coastal waters into immediate coast vicinity and the Florida Keys into portions of southern Florida, Friday through Friday night. This may be accompanied by at least some risk for damaging wind gusts and a tornado or two. ...Synopsis... Blocking centered over the northeastern Pacific may generally persist through this period, but models suggest that some weakening may commence as a more progressive regime gradually develops across the central toward eastern mid-latitude Pacific. Models vary concerning the extent of this weakening, and this probably will have at least some impact on developments within the broadly confluent split downstream flow across North America. In general, another cold intrusion is forecast to the lee of the Rockies, as far south as the Texas Panhandle/Red River Valley and Mid South, and as far east as the Ohio Valley/lower Great Lakes by 12Z Saturday. This will occur to the west and south of a mid-level low becoming quasi-stationary near the southwestern shores of Hudson Bay. In lower latitudes, mid-level troughing is generally forecast to slowly progress east of the lower Mississippi Valley/northwestern Gulf coast region Friday, with one increasingly sheared perturbation shifting toward the southern Appalachians and another perhaps more notable perturbation digging into the north central/northeastern Gulf by early Saturday. Models differ concerning these features, and the larger-scale troughing will be preceded by a subtropical perturbation progressing across the Florida peninsula early Friday. And there is substantive spread concerning the further evolution of a broad, modest area of surface low pressure overspreading the eastern Gulf Coast/South Atlantic Coast by the end of the period. ...Southeast... An initially dry/potentially cool low-level environment across much of the eastern Gulf Coast into Florida peninsula will precede considerable convective development expected to be ongoing at 12Z Friday across the north central Gulf coast/lower Mississippi Valley vicinity, and across the central into northeastern Gulf of Mexico. As this activity continues to spread eastward and northeastward with the large-scale forcing for ascent, forecast soundings indicate a tendency for profiles to trend saturated moist adiabatic. However, there is at least some signal within model output that a warm front may advance from the southeastern Gulf of Mexico across the Florida Keys and portions of the southern Florida peninsula, coincident with an organized cluster of thunderstorms which could pose a risk for producing damaging wind gusts and a couple of tornadoes. Thereafter, trailing outflow may provide a focus for continuing thunderstorm development in the presence of strong deep-layer shear. Additional strong to severe thunderstorm development is possible within the warm sector of the developing area of low pressure, across the northeastern/eastern Gulf of Mexico, some of which might impact the coastal waters and immediate coast Friday night. However, the extent of this potential will probably depend on the details of the surface low evolution, which remains unclear at this time. ..Kerr.. 03/20/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0154 AM CDT Wed Mar 20 2024 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... ...Synopsis... Predominantly zonal mid-level flow is anticipated across the U.S. on Thursday, leading to generally mild conditions and low fire-weather concerns. Locally drier and windier conditions could develop in portions of the Southern and Central Plains, but confidence is currently too low in these scenarios to warrant any Elevated areas at this time. ...NE Panhandle and vicinity... Confidence has increased in a surface cyclone developing in the lee of the Rockies near the NE Panhandle throughout the day on Thursday. This will support some moisture return across the Southern Plains, as well as relatively dry, downsloping flow in the NE Panhandle, eastern WY, and northeastern CO. Deep, well-mixed boundary layers could yield relative humidities around 20 percent across the region with sustained winds of 15-20 mph. Fuels do not appear to be critically dry, but could support some fire spread (e.g., ERCs approaching the 70-80th percentiles in some areas). No Elevated area is delineated in this outlook due to slightly lower confidence in the location of the surface cyclone and attendant moisture gradients; guidance will be monitored for possible future inclusion. ...West TX... An area of slightly stronger mid-level flow is expected to overspread West TX on Thursday afternoon, contributing to locally gustier surface conditions. Wind speeds around 15-20 mph and relative humidities around 15-20 percent could contribute to local Elevated fire-weather conditions. However, highlighting a particular area is currently difficult due to the chance for wetting precipitation Wednesday night into Thursday morning. Confidence in such a scenario will continue to be monitored, possibly warranting areal delineations in future outlooks. ..Flournoy.. 03/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more