SPC Apr 11, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Thu Apr 11 2024 Valid 111300Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR EASTERN OHIO AND NORTHWEST WEST VIRGINIA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHERN GEORGIA INTO NORTH AND CENTRAL PARTS OF FLORIDA... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are possible across the upper Ohio River Valley and parts of the Appalachians this afternoon. Scattered damaging winds and a couple of tornadoes are possible in far southern Georgia into central Florida, mainly this morning through early afternoon. ...Synopsis... Water-vapor imagery this morning shows a potent mid-level low/trough centered near the AR/MS/TN border with an upstream trough over the Upper Midwest forecast to phase with the Southeast trough. A cyclone near the TN/MS border will deepen as it develops north-northeast into the Lower Great Lakes by early evening. A trailing surface cold front will push east across portions of the Southeast/southern Appalachians during the day, before clearing the Southeast coast by early Friday morning. ...Upper OH River Valley... Considerable uncertainty remains for this forecast in terms of the magnitude of destabilization across the OH Valley late this morning through the afternoon. This uncertainty is primarily due to low cloud cover and weak capping resulting in scattered showers/low-topped thunderstorm activity and the potential to remain relatively cool in the boundary layer. However, mid-level dry air evident in water-vapor imagery is wrapping through the base of the mid-level low/trough over TN, and this mid-level dry intrusion forecast to spread northeast into portions of the Upper OH Valley. Weak instability coupled with some enlargement of the hodograph can support an environment in which discrete cells and semi-discrete clusters evolve into supercells. A few tornadoes are possible if stronger updrafts/supercells manage to develop, in addition to an accompanying threat for damaging gusts and perhaps marginally severe hail. ...Florida/Georgia... Ongoing pre-frontal broken band of strong to severe thunderstorms over north FL and the eastern Gulf of Mexico will gradually shift east across the northern half of the Peninsula through the morning and into the afternoon. The northern rim of rich low-level moisture (upper 60s to lower 70s deg F surface dewpoints) have advected into north FL early this morning. Although lapse rates will remain modest, it appears the richer moisture will contribute to adequate surface-based buoyancy (500-1250 J/kg MLCAPE) across the northern half of the Peninsula today. The Jacksonville and Tampa 88D VAD wind profiles are quite strong this morning and will likely remain so through the early afternoon as the larger-scale mid-level trough pivots eastward over the FL Peninsula by early evening. The risk for a couple of tornadoes and damaging gusts will likely maximize through the midday before the thunderstorm band moves offshore and forcing for ascent gradually abates by late afternoon as the synoptic low lifts well to the north. ...Mid-Atlantic states into Carolinas... A less focused and more conditional severe risk seems evident for the Carolinas later this afternoon and northward into the Mid-Atlantic states this evening as the upper trough encroaches on the general region. A broad warm-air advection regime north of the FL/GA early-day MCS will slowly destabilize today, aided in part by lower 60 deg F dewpoints north, mid to upper 60s south. Long hodographs will favor storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, mainly over parts of western VA, with lower coverage expected farther east over the coastal plain/Delmarva. ..Smith/Mosier.. 04/11/2024 Read more

SPC Apr 11, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Thu Apr 11 2024 Valid 111300Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR EASTERN OHIO AND NORTHWEST WEST VIRGINIA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHERN GEORGIA INTO NORTH AND CENTRAL PARTS OF FLORIDA... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are possible across the upper Ohio River Valley and parts of the Appalachians this afternoon. Scattered damaging winds and a couple of tornadoes are possible in far southern Georgia into central Florida, mainly this morning through early afternoon. ...Synopsis... Water-vapor imagery this morning shows a potent mid-level low/trough centered near the AR/MS/TN border with an upstream trough over the Upper Midwest forecast to phase with the Southeast trough. A cyclone near the TN/MS border will deepen as it develops north-northeast into the Lower Great Lakes by early evening. A trailing surface cold front will push east across portions of the Southeast/southern Appalachians during the day, before clearing the Southeast coast by early Friday morning. ...Upper OH River Valley... Considerable uncertainty remains for this forecast in terms of the magnitude of destabilization across the OH Valley late this morning through the afternoon. This uncertainty is primarily due to low cloud cover and weak capping resulting in scattered showers/low-topped thunderstorm activity and the potential to remain relatively cool in the boundary layer. However, mid-level dry air evident in water-vapor imagery is wrapping through the base of the mid-level low/trough over TN, and this mid-level dry intrusion forecast to spread northeast into portions of the Upper OH Valley. Weak instability coupled with some enlargement of the hodograph can support an environment in which discrete cells and semi-discrete clusters evolve into supercells. A few tornadoes are possible if stronger updrafts/supercells manage to develop, in addition to an accompanying threat for damaging gusts and perhaps marginally severe hail. ...Florida/Georgia... Ongoing pre-frontal broken band of strong to severe thunderstorms over north FL and the eastern Gulf of Mexico will gradually shift east across the northern half of the Peninsula through the morning and into the afternoon. The northern rim of rich low-level moisture (upper 60s to lower 70s deg F surface dewpoints) have advected into north FL early this morning. Although lapse rates will remain modest, it appears the richer moisture will contribute to adequate surface-based buoyancy (500-1250 J/kg MLCAPE) across the northern half of the Peninsula today. The Jacksonville and Tampa 88D VAD wind profiles are quite strong this morning and will likely remain so through the early afternoon as the larger-scale mid-level trough pivots eastward over the FL Peninsula by early evening. The risk for a couple of tornadoes and damaging gusts will likely maximize through the midday before the thunderstorm band moves offshore and forcing for ascent gradually abates by late afternoon as the synoptic low lifts well to the north. ...Mid-Atlantic states into Carolinas... A less focused and more conditional severe risk seems evident for the Carolinas later this afternoon and northward into the Mid-Atlantic states this evening as the upper trough encroaches on the general region. A broad warm-air advection regime north of the FL/GA early-day MCS will slowly destabilize today, aided in part by lower 60 deg F dewpoints north, mid to upper 60s south. Long hodographs will favor storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, mainly over parts of western VA, with lower coverage expected farther east over the coastal plain/Delmarva. ..Smith/Mosier.. 04/11/2024 Read more

SPC Apr 11, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Thu Apr 11 2024 Valid 111300Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR EASTERN OHIO AND NORTHWEST WEST VIRGINIA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHERN GEORGIA INTO NORTH AND CENTRAL PARTS OF FLORIDA... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are possible across the upper Ohio River Valley and parts of the Appalachians this afternoon. Scattered damaging winds and a couple of tornadoes are possible in far southern Georgia into central Florida, mainly this morning through early afternoon. ...Synopsis... Water-vapor imagery this morning shows a potent mid-level low/trough centered near the AR/MS/TN border with an upstream trough over the Upper Midwest forecast to phase with the Southeast trough. A cyclone near the TN/MS border will deepen as it develops north-northeast into the Lower Great Lakes by early evening. A trailing surface cold front will push east across portions of the Southeast/southern Appalachians during the day, before clearing the Southeast coast by early Friday morning. ...Upper OH River Valley... Considerable uncertainty remains for this forecast in terms of the magnitude of destabilization across the OH Valley late this morning through the afternoon. This uncertainty is primarily due to low cloud cover and weak capping resulting in scattered showers/low-topped thunderstorm activity and the potential to remain relatively cool in the boundary layer. However, mid-level dry air evident in water-vapor imagery is wrapping through the base of the mid-level low/trough over TN, and this mid-level dry intrusion forecast to spread northeast into portions of the Upper OH Valley. Weak instability coupled with some enlargement of the hodograph can support an environment in which discrete cells and semi-discrete clusters evolve into supercells. A few tornadoes are possible if stronger updrafts/supercells manage to develop, in addition to an accompanying threat for damaging gusts and perhaps marginally severe hail. ...Florida/Georgia... Ongoing pre-frontal broken band of strong to severe thunderstorms over north FL and the eastern Gulf of Mexico will gradually shift east across the northern half of the Peninsula through the morning and into the afternoon. The northern rim of rich low-level moisture (upper 60s to lower 70s deg F surface dewpoints) have advected into north FL early this morning. Although lapse rates will remain modest, it appears the richer moisture will contribute to adequate surface-based buoyancy (500-1250 J/kg MLCAPE) across the northern half of the Peninsula today. The Jacksonville and Tampa 88D VAD wind profiles are quite strong this morning and will likely remain so through the early afternoon as the larger-scale mid-level trough pivots eastward over the FL Peninsula by early evening. The risk for a couple of tornadoes and damaging gusts will likely maximize through the midday before the thunderstorm band moves offshore and forcing for ascent gradually abates by late afternoon as the synoptic low lifts well to the north. ...Mid-Atlantic states into Carolinas... A less focused and more conditional severe risk seems evident for the Carolinas later this afternoon and northward into the Mid-Atlantic states this evening as the upper trough encroaches on the general region. A broad warm-air advection regime north of the FL/GA early-day MCS will slowly destabilize today, aided in part by lower 60 deg F dewpoints north, mid to upper 60s south. Long hodographs will favor storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, mainly over parts of western VA, with lower coverage expected farther east over the coastal plain/Delmarva. ..Smith/Mosier.. 04/11/2024 Read more

SPC Apr 11, 2024 1300 UTC Day 1 Convective Outlook

1 year 4 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Thu Apr 11 2024 Valid 111300Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR EASTERN OHIO AND NORTHWEST WEST VIRGINIA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHERN GEORGIA INTO NORTH AND CENTRAL PARTS OF FLORIDA... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are possible across the upper Ohio River Valley and parts of the Appalachians this afternoon. Scattered damaging winds and a couple of tornadoes are possible in far southern Georgia into central Florida, mainly this morning through early afternoon. ...Synopsis... Water-vapor imagery this morning shows a potent mid-level low/trough centered near the AR/MS/TN border with an upstream trough over the Upper Midwest forecast to phase with the Southeast trough. A cyclone near the TN/MS border will deepen as it develops north-northeast into the Lower Great Lakes by early evening. A trailing surface cold front will push east across portions of the Southeast/southern Appalachians during the day, before clearing the Southeast coast by early Friday morning. ...Upper OH River Valley... Considerable uncertainty remains for this forecast in terms of the magnitude of destabilization across the OH Valley late this morning through the afternoon. This uncertainty is primarily due to low cloud cover and weak capping resulting in scattered showers/low-topped thunderstorm activity and the potential to remain relatively cool in the boundary layer. However, mid-level dry air evident in water-vapor imagery is wrapping through the base of the mid-level low/trough over TN, and this mid-level dry intrusion forecast to spread northeast into portions of the Upper OH Valley. Weak instability coupled with some enlargement of the hodograph can support an environment in which discrete cells and semi-discrete clusters evolve into supercells. A few tornadoes are possible if stronger updrafts/supercells manage to develop, in addition to an accompanying threat for damaging gusts and perhaps marginally severe hail. ...Florida/Georgia... Ongoing pre-frontal broken band of strong to severe thunderstorms over north FL and the eastern Gulf of Mexico will gradually shift east across the northern half of the Peninsula through the morning and into the afternoon. The northern rim of rich low-level moisture (upper 60s to lower 70s deg F surface dewpoints) have advected into north FL early this morning. Although lapse rates will remain modest, it appears the richer moisture will contribute to adequate surface-based buoyancy (500-1250 J/kg MLCAPE) across the northern half of the Peninsula today. The Jacksonville and Tampa 88D VAD wind profiles are quite strong this morning and will likely remain so through the early afternoon as the larger-scale mid-level trough pivots eastward over the FL Peninsula by early evening. The risk for a couple of tornadoes and damaging gusts will likely maximize through the midday before the thunderstorm band moves offshore and forcing for ascent gradually abates by late afternoon as the synoptic low lifts well to the north. ...Mid-Atlantic states into Carolinas... A less focused and more conditional severe risk seems evident for the Carolinas later this afternoon and northward into the Mid-Atlantic states this evening as the upper trough encroaches on the general region. A broad warm-air advection regime north of the FL/GA early-day MCS will slowly destabilize today, aided in part by lower 60 deg F dewpoints north, mid to upper 60s south. Long hodographs will favor storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, mainly over parts of western VA, with lower coverage expected farther east over the coastal plain/Delmarva. ..Smith/Mosier.. 04/11/2024 Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Apr 11, 2024 Day 4-8 Severe Weather Outlook

1 year 4 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Thu Apr 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... ...Significant severe weather episode possible late afternoon and evening on Monday... A mid/upper low over the central CA vicinity at 12Z Sunday should evolve into an open wave as it ejects across the Southwest and into the central Great Plains by around Tuesday morning. As it crosses the Rockies onto the High Plains, the tropospheric flow field will amplify with substantial lee cyclogenesis in the central High Plains on Monday afternoon. While a moderate amount of spread persists across respective ensemble systems, 00Z deterministic runs have converged towards greater agreement with the aforementioned scenario through D5, with progressively lower predictability in D6-8. With about 3 days of persistent low-level moisture modification from the western Gulf beneath an extensive elevated mixed layer, the northern extent of mid 60s surface dew points should reach into most of OK east of the dryline by Monday afternoon. Late afternoon thunderstorm initiation along the dryline appears probable in the eastern TX Panhandle/western north TX to western OK vicinity, within a kinematic and thermodynamic profile favorable for strong supercells. Convective development will blossom both south and especially north extent during the evening across the central and southern Great Plains. For this outlook, have expanded the 30 percent area to highlight the greater spatial confidence in a substantial severe weather episode. Despite increasing predictability concerns and the impact of prior day convection, very strong flow fields should persist into at least the first half of D6/Tuesday as a deep surface cyclone pivots northeast towards the Upper MS Valley vicinity. While instability will be weaker compared to Monday, organized severe potential is evident within an arc from a portion of the Upper MS Valley to the Mid-South. In the wake of this lead system, the shortwave trough digging into the Pacific Northwest may carve out a broad, positive-tilt trough in the West by mid-week. Consensus of guidance suggests that rich low-level moisture over the southern Great Plains will not be scoured by the lead wave. This may yield daily bouts of severe thunderstorms across parts of the central and southern Great Plains late in the period and beyond. Predictability for individual day highlights is too low to warrant 15 percent probabilities yet. Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

1 year 4 months ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 AM CDT Thu Apr 11 2024 Valid 121200Z - 131200Z ...Synopsis... Fire weather conditions are anticipated across a broad swath of the Southwest and southern High Plains on Friday afternoon. However, the fire weather threat will most likely be focused across parts of New Mexico and the OK/TX Panhandles where the best overlap of fire weather conditions and receptive fuels is anticipated. Surface high pressure is forecast to shift from the central Plains into the northwest Gulf of Mexico. Concurrently, the approach of an upper wave off the southern CA coast will lead to broad surface pressure falls across the southern Great Basin into the southern High Plains, resulting in breezy pressure gradient winds. ...New Mexico and adjacent areas of the OK/TX Panhandles... Latest guidance continues to show a signal for 15-20 mph winds across a broad swath of eastern NM and west TX. Low-level trajectories emanating off the terrain of northern Mexico, combined with a recent frontal intrusion into the western Gulf, should maintain dry conditions across the southern High Plains with RH values in the 10-20% range. Elevated conditions are expected with localized critical conditions possible Friday afternoon. Despite the potential for widespread fire weather conditions, the risk area is confined to locations that have not seen wetting rainfall over the past few days (and hence should have the most receptive fuels). Based on recent fuel analyses, ERCs further west into the Southwest/Great Basin are near/below the 50th percentile, which precludes a more widespread risk area (though fuel trends will be monitored). ..Moore.. 04/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more