Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 AM CDT Wed Mar 27 2024 Valid 271300Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NEAR-COASTAL SOUTHEAST...AS WELL AS PORTIONS OF CENTRAL AND NORTH TEXAS... ...SUMMARY... Isolated severe hail and damaging winds are possible over parts of the near-coastal Southeast, as well as portions of central and north Texas. ...Synopsis... A vast area of the CONUS begins the period with cyclonic mid/upper- level flow, thanks to nearly phased northern- and southern-stream synoptic troughs. The southern one is apparent in moisture-channel imagery from eastern NM to the Big Bend region of west TX, then over Coahuila, and should move eastward to AR, east TX and the northwestern Gulf by 00Z. The northern one is anchored by a 500-mb cyclone centered initially over northwestern MN, forecast to pivot to near Thunder Bay, ON, by 00Z, then northeastward to between Lake Superior and James Bay around 12Z. By then, phased troughing will extend from there across Lake Michigan and the lower Ohio Valley to the southern-stream perturbation over parts of AL, southeastern LA and the north-central/west-central Gulf. At the surface, 11Z analysis depicted an occluded low over northern ON, with an occluded/cold front to near BUF, PIT, and BKW, to a triple-point low near AGS. A cold front extended from there southwestward across the AAF area to the central/southwestern Gulf. A warm front was drawn from the southern low east-southeastward between SAV-CHS. The warm front should shift northeastward across coastal SC and the Low Country today. Another frontal-wave low may form tonight over SC then move offshore. The cold front should move slowly southeastward, reaching near an XMR-EYW line by 12Z tomorrow. ...Southeast CONUS... An ongoing belt of precip, with embedded/scattered thunderstorms, should continue to shift slowly eastward across the area, in step with (and near the position of) the front. The most intense cells will be capable of damaging gusts -- especially on and ahead of the boundary -- as well as severe hail. That includes a semi-organized, bowing storm cluster moving inland from the FL coastal bend, for another hour or so until it encounters substantially more stable air sampled by the 12Z TBW and JAX RAOBs. The near-surface layer -- initially stable over land from prior nocturnal cooling -- should undergo both gradual diabatic heating through anvil-cloud cover, and warm/moist advection through the afternoon. This will erode the morning stable layer and support peak preconvective/prefrontal MLCAPE of 1500-2000 J/Kg over parts of northern FL, and 1000-1500 J/kg over eastern GA and parts of SC. Flow aloft will remain strongly parallel to the front and the convective plume, continuing a messy convective character with embedded thunderstorms. Forecast hodographs support a blend of sporadic left- and right-moving supercells, and mainly organized multicells, with stronger shear and buoyancy but somewhat weaker lift over southern parts of the outlook area. As the threat appears sporadic and spatially isolated -- not very well-focused in time or within the broader precip swath -- probabilities are held at marginal unconditional thresholds for now. ...Central/north TX... Widely scattered thunderstorms are possible for a few hours this afternoon into early evening, moving eastward to southeastward, with isolated severe hail and strong to marginally severe gusts possible. An area of surface low pressure over eastern NM -- initially tied to lee troughing that extends well poleward into AB -- will split off and move southeastward over northwest/north-central TX this afternoon in response to the perturbation aloft, with a trough/ convergence zone to the south or south-southeast across central TX. These features should provide enough lift for convection, amidst minimal capping. As the mid/upper trough shifts toward and over the area, very cold air aloft (500-mb temperatures at or below -25 deg C) will contribute to steep midlevel lapse rates exceeding 8 deg C/km. Despite being seemingly cool at the surface and well behind the cold front, diabatic heating and residual moisture (dewpoints generally mid 30s to mid 40s F) should erode MLCINH by mid/late afternoon, with 300-700 J/kg MLCAPE possible. Though low-level flow will be weak, enough deep shear should exist to support multicells and at least transient supercell structures, atop a well-mixed subcloud layer. The threat should wane by about 03Z as the near-surface layer stabilizes and coverage/intensity of what had been mostly diurnally driven convection diminishes. ..Edwards/Leitman.. 03/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 AM CDT Wed Mar 27 2024 Valid 271300Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NEAR-COASTAL SOUTHEAST...AS WELL AS PORTIONS OF CENTRAL AND NORTH TEXAS... ...SUMMARY... Isolated severe hail and damaging winds are possible over parts of the near-coastal Southeast, as well as portions of central and north Texas. ...Synopsis... A vast area of the CONUS begins the period with cyclonic mid/upper- level flow, thanks to nearly phased northern- and southern-stream synoptic troughs. The southern one is apparent in moisture-channel imagery from eastern NM to the Big Bend region of west TX, then over Coahuila, and should move eastward to AR, east TX and the northwestern Gulf by 00Z. The northern one is anchored by a 500-mb cyclone centered initially over northwestern MN, forecast to pivot to near Thunder Bay, ON, by 00Z, then northeastward to between Lake Superior and James Bay around 12Z. By then, phased troughing will extend from there across Lake Michigan and the lower Ohio Valley to the southern-stream perturbation over parts of AL, southeastern LA and the north-central/west-central Gulf. At the surface, 11Z analysis depicted an occluded low over northern ON, with an occluded/cold front to near BUF, PIT, and BKW, to a triple-point low near AGS. A cold front extended from there southwestward across the AAF area to the central/southwestern Gulf. A warm front was drawn from the southern low east-southeastward between SAV-CHS. The warm front should shift northeastward across coastal SC and the Low Country today. Another frontal-wave low may form tonight over SC then move offshore. The cold front should move slowly southeastward, reaching near an XMR-EYW line by 12Z tomorrow. ...Southeast CONUS... An ongoing belt of precip, with embedded/scattered thunderstorms, should continue to shift slowly eastward across the area, in step with (and near the position of) the front. The most intense cells will be capable of damaging gusts -- especially on and ahead of the boundary -- as well as severe hail. That includes a semi-organized, bowing storm cluster moving inland from the FL coastal bend, for another hour or so until it encounters substantially more stable air sampled by the 12Z TBW and JAX RAOBs. The near-surface layer -- initially stable over land from prior nocturnal cooling -- should undergo both gradual diabatic heating through anvil-cloud cover, and warm/moist advection through the afternoon. This will erode the morning stable layer and support peak preconvective/prefrontal MLCAPE of 1500-2000 J/Kg over parts of northern FL, and 1000-1500 J/kg over eastern GA and parts of SC. Flow aloft will remain strongly parallel to the front and the convective plume, continuing a messy convective character with embedded thunderstorms. Forecast hodographs support a blend of sporadic left- and right-moving supercells, and mainly organized multicells, with stronger shear and buoyancy but somewhat weaker lift over southern parts of the outlook area. As the threat appears sporadic and spatially isolated -- not very well-focused in time or within the broader precip swath -- probabilities are held at marginal unconditional thresholds for now. ...Central/north TX... Widely scattered thunderstorms are possible for a few hours this afternoon into early evening, moving eastward to southeastward, with isolated severe hail and strong to marginally severe gusts possible. An area of surface low pressure over eastern NM -- initially tied to lee troughing that extends well poleward into AB -- will split off and move southeastward over northwest/north-central TX this afternoon in response to the perturbation aloft, with a trough/ convergence zone to the south or south-southeast across central TX. These features should provide enough lift for convection, amidst minimal capping. As the mid/upper trough shifts toward and over the area, very cold air aloft (500-mb temperatures at or below -25 deg C) will contribute to steep midlevel lapse rates exceeding 8 deg C/km. Despite being seemingly cool at the surface and well behind the cold front, diabatic heating and residual moisture (dewpoints generally mid 30s to mid 40s F) should erode MLCINH by mid/late afternoon, with 300-700 J/kg MLCAPE possible. Though low-level flow will be weak, enough deep shear should exist to support multicells and at least transient supercell structures, atop a well-mixed subcloud layer. The threat should wane by about 03Z as the near-surface layer stabilizes and coverage/intensity of what had been mostly diurnally driven convection diminishes. ..Edwards/Leitman.. 03/27/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Mar 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... An upper trough/low should continue to move south-southeastward over the western states on Day 4/Saturday. Over much of the central CONUS, upper ridging should generally prevail, with a gradual northward advance of low-level moisture across the southern Plains. Although a plume of elevated instability should accompany this moisture return, a cap is expected to suppress robust convective development Saturday. On Day 5/Sunday, the upper trough/low over the western CONUS should slowly advance eastward across the Southwest. But, there are still some differences in various guidance with the evolution of this trough/low. Some GEFS ensemble members show a slower ejection, with a closed 500-mb isohypse remaining over the West. Other members align more with the deterministic ECMWF is showing a more open wave, but with a positive tilt into the northern/central Plains. Another potentially complicating factor is a northern-stream upper trough, which may phase with the lower-latitude trough and help induce stronger cyclogenesis across the mid MS Valley/Midwest around Day 6/Monday. Even with these continued differences, it appears that severe potential should gradually increase from Sunday into Monday across parts of the southern/central Plains, mid MO into mid MS Valleys, and perhaps also into the OH Valley/Midwest. For Sunday, some severe potential may be focused across parts of MO into IL along and near a sharpening surface warm front. Mid-level height tendencies look to remain neutral through Sunday evening across this area, with nebulous large-scale ascent. Even so, low-level warm advection may help initially elevated convection to develop across MO in a moderate instability and strong deep-layer shear environment. If this occurs, then some severe threat may continue eastward into IL through Sunday evening. At this point, too much uncertainty exists regarding thunderstorm initiation and coverage to include a focused 15% severe area for Sunday. A larger area of severe potential may be realized on Monday from parts of the southern/central Plains into the mid MS and OH Valleys. This will be largely dependent on the timing of ejection of the upper trough over the Southwest, and whether it can phase any with a northern-stream trough moving southeastward out of central Canada. Regardless, a broad warm sector, with 60s surface dewpoints, should be in place from TX/OK east of a dryline and northward to a warm front located somewhere in the vicinity of the OH Valley. The exact placement of these surface features remains rather uncertain Monday, as does the potential strength and northeastward track of a surface low across the mid MS and OH Valleys. Deep-layer shear appears strong enough to support organized severe thunderstorms, and consideration was given to adding a broad 15% severe area for Monday. But, there still seems to be too much spread in possible solutions with the upper trough to introduce an area yet. Finally, some severe threat may continue on Day 7/Tuesday along and ahead of a cold front moving across parts of the Southeast and eastern states. But, predictability remains very low at this extended time frame. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed Mar 27 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely on Friday. ...Synopsis and Discussion... An upper trough/low should dig southward along or very near the northern/central CA Coast Friday. Isolated lightning flashes may occur across parts of coastal central CA through the period, as cold mid-level temperatures aid in the development of weak MUCAPE. A separate area of isolated thunderstorm potential, mainly related to orographic lift, is also apparent over portions of central Rockies. Farther east, a modified Gulf airmass should slowly advance northward from the southern Plains into parts of the mid MS Valley and Upper Midwest by Friday evening. The northern extent of this low-level moisture plume is expected to remain rather shallow and limited, with surface dewpoints no greater than the low 50s. Still, a weak shortwave trough forecast to eject across the northern/ central Plains should aid in weak cyclogenesis across the Upper Midwest. It could also provide sufficient lift, in tandem with a strengthening southwesterly low-level jet, to support thunderstorm development mainly Friday night from parts of the mid MO Valley into the Midwest and southern Great Lakes. Even though deep-layer shear is forecast to become strong in this time frame, convection will probably tend to remain elevated. Generally weak MUCAPE should limit the threat for severe-caliber hail, although small hail with the most robust updrafts appears possible. ..Gleason.. 03/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed Mar 27 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely on Friday. ...Synopsis and Discussion... An upper trough/low should dig southward along or very near the northern/central CA Coast Friday. Isolated lightning flashes may occur across parts of coastal central CA through the period, as cold mid-level temperatures aid in the development of weak MUCAPE. A separate area of isolated thunderstorm potential, mainly related to orographic lift, is also apparent over portions of central Rockies. Farther east, a modified Gulf airmass should slowly advance northward from the southern Plains into parts of the mid MS Valley and Upper Midwest by Friday evening. The northern extent of this low-level moisture plume is expected to remain rather shallow and limited, with surface dewpoints no greater than the low 50s. Still, a weak shortwave trough forecast to eject across the northern/ central Plains should aid in weak cyclogenesis across the Upper Midwest. It could also provide sufficient lift, in tandem with a strengthening southwesterly low-level jet, to support thunderstorm development mainly Friday night from parts of the mid MO Valley into the Midwest and southern Great Lakes. Even though deep-layer shear is forecast to become strong in this time frame, convection will probably tend to remain elevated. Generally weak MUCAPE should limit the threat for severe-caliber hail, although small hail with the most robust updrafts appears possible. ..Gleason.. 03/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed Mar 27 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely on Friday. ...Synopsis and Discussion... An upper trough/low should dig southward along or very near the northern/central CA Coast Friday. Isolated lightning flashes may occur across parts of coastal central CA through the period, as cold mid-level temperatures aid in the development of weak MUCAPE. A separate area of isolated thunderstorm potential, mainly related to orographic lift, is also apparent over portions of central Rockies. Farther east, a modified Gulf airmass should slowly advance northward from the southern Plains into parts of the mid MS Valley and Upper Midwest by Friday evening. The northern extent of this low-level moisture plume is expected to remain rather shallow and limited, with surface dewpoints no greater than the low 50s. Still, a weak shortwave trough forecast to eject across the northern/ central Plains should aid in weak cyclogenesis across the Upper Midwest. It could also provide sufficient lift, in tandem with a strengthening southwesterly low-level jet, to support thunderstorm development mainly Friday night from parts of the mid MO Valley into the Midwest and southern Great Lakes. Even though deep-layer shear is forecast to become strong in this time frame, convection will probably tend to remain elevated. Generally weak MUCAPE should limit the threat for severe-caliber hail, although small hail with the most robust updrafts appears possible. ..Gleason.. 03/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed Mar 27 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely on Friday. ...Synopsis and Discussion... An upper trough/low should dig southward along or very near the northern/central CA Coast Friday. Isolated lightning flashes may occur across parts of coastal central CA through the period, as cold mid-level temperatures aid in the development of weak MUCAPE. A separate area of isolated thunderstorm potential, mainly related to orographic lift, is also apparent over portions of central Rockies. Farther east, a modified Gulf airmass should slowly advance northward from the southern Plains into parts of the mid MS Valley and Upper Midwest by Friday evening. The northern extent of this low-level moisture plume is expected to remain rather shallow and limited, with surface dewpoints no greater than the low 50s. Still, a weak shortwave trough forecast to eject across the northern/ central Plains should aid in weak cyclogenesis across the Upper Midwest. It could also provide sufficient lift, in tandem with a strengthening southwesterly low-level jet, to support thunderstorm development mainly Friday night from parts of the mid MO Valley into the Midwest and southern Great Lakes. Even though deep-layer shear is forecast to become strong in this time frame, convection will probably tend to remain elevated. Generally weak MUCAPE should limit the threat for severe-caliber hail, although small hail with the most robust updrafts appears possible. ..Gleason.. 03/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Wed Mar 27 2024 Valid 291200Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely on Friday. ...Synopsis and Discussion... An upper trough/low should dig southward along or very near the northern/central CA Coast Friday. Isolated lightning flashes may occur across parts of coastal central CA through the period, as cold mid-level temperatures aid in the development of weak MUCAPE. A separate area of isolated thunderstorm potential, mainly related to orographic lift, is also apparent over portions of central Rockies. Farther east, a modified Gulf airmass should slowly advance northward from the southern Plains into parts of the mid MS Valley and Upper Midwest by Friday evening. The northern extent of this low-level moisture plume is expected to remain rather shallow and limited, with surface dewpoints no greater than the low 50s. Still, a weak shortwave trough forecast to eject across the northern/ central Plains should aid in weak cyclogenesis across the Upper Midwest. It could also provide sufficient lift, in tandem with a strengthening southwesterly low-level jet, to support thunderstorm development mainly Friday night from parts of the mid MO Valley into the Midwest and southern Great Lakes. Even though deep-layer shear is forecast to become strong in this time frame, convection will probably tend to remain elevated. Generally weak MUCAPE should limit the threat for severe-caliber hail, although small hail with the most robust updrafts appears possible. ..Gleason.. 03/27/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Mar 27 2024 Valid 281200Z - 291200Z ...Synopsis... A mid-level trough will approach the Rocky Mountains tomorrow (Thursday), with surface lee troughing and associated dry downslope flow anticipated across portions of the southern High Plains. For the afternoon hours, the latest guidance consensus depicts 15+ mph sustained south-southwesterly winds coinciding with 15-20 percent RH across eastern New Mexico into western Texas. With fuels being marginally receptive to wildfire spread, Elevated highlights have been introduced. ..Squitieri.. 03/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Mar 27 2024 Valid 281200Z - 291200Z ...Synopsis... A mid-level trough will approach the Rocky Mountains tomorrow (Thursday), with surface lee troughing and associated dry downslope flow anticipated across portions of the southern High Plains. For the afternoon hours, the latest guidance consensus depicts 15+ mph sustained south-southwesterly winds coinciding with 15-20 percent RH across eastern New Mexico into western Texas. With fuels being marginally receptive to wildfire spread, Elevated highlights have been introduced. ..Squitieri.. 03/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Mar 27 2024 Valid 281200Z - 291200Z ...Synopsis... A mid-level trough will approach the Rocky Mountains tomorrow (Thursday), with surface lee troughing and associated dry downslope flow anticipated across portions of the southern High Plains. For the afternoon hours, the latest guidance consensus depicts 15+ mph sustained south-southwesterly winds coinciding with 15-20 percent RH across eastern New Mexico into western Texas. With fuels being marginally receptive to wildfire spread, Elevated highlights have been introduced. ..Squitieri.. 03/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Mar 27 2024 Valid 281200Z - 291200Z ...Synopsis... A mid-level trough will approach the Rocky Mountains tomorrow (Thursday), with surface lee troughing and associated dry downslope flow anticipated across portions of the southern High Plains. For the afternoon hours, the latest guidance consensus depicts 15+ mph sustained south-southwesterly winds coinciding with 15-20 percent RH across eastern New Mexico into western Texas. With fuels being marginally receptive to wildfire spread, Elevated highlights have been introduced. ..Squitieri.. 03/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Mar 27 2024 Valid 281200Z - 291200Z ...Synopsis... A mid-level trough will approach the Rocky Mountains tomorrow (Thursday), with surface lee troughing and associated dry downslope flow anticipated across portions of the southern High Plains. For the afternoon hours, the latest guidance consensus depicts 15+ mph sustained south-southwesterly winds coinciding with 15-20 percent RH across eastern New Mexico into western Texas. With fuels being marginally receptive to wildfire spread, Elevated highlights have been introduced. ..Squitieri.. 03/27/2024 ...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 0149 AM CDT Wed Mar 27 2024 Valid 271200Z - 281200Z ...Synopsis... Deep-layer northwesterly flow will overspread the southern High Plains as a mid-level trough traverses the Lower Mississippi Valley today. Dry downslope flow will develop across southeastern New Mexico into western Texas this afternoon, promoting conditions favorable for wildfire spread. By afternoon peak heating, 20-25 mph sustained west-northwesterly surface winds will overlap with 10-15 percent RH for at least a few hours. Given that these Critical meteorological surface conditions will overlap fuels that are at least marginally receptive to fire spread, "high-end" Elevated highlights have been maintained. ..Squitieri.. 03/27/2024 ...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 0149 AM CDT Wed Mar 27 2024 Valid 271200Z - 281200Z ...Synopsis... Deep-layer northwesterly flow will overspread the southern High Plains as a mid-level trough traverses the Lower Mississippi Valley today. Dry downslope flow will develop across southeastern New Mexico into western Texas this afternoon, promoting conditions favorable for wildfire spread. By afternoon peak heating, 20-25 mph sustained west-northwesterly surface winds will overlap with 10-15 percent RH for at least a few hours. Given that these Critical meteorological surface conditions will overlap fuels that are at least marginally receptive to fire spread, "high-end" Elevated highlights have been maintained. ..Squitieri.. 03/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more