Severe Storms

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0333 AM CST Thu Feb 22 2024 Valid 251200Z - 011200Z ...DISCUSSION... Medium-range models continue to show a powerful mid- to upper-level trough ejecting into the central U.S. by late Tuesday into Wednesday. A deep cyclone is currently progged by most ensemble members to move from the central Great Plains into the Great Lakes vicinity. Preceding this upper trough, an antecedent re-charging of steep lapse rates associated with an elevated mixed layer over the southern High Plains is forecast. A few days of airmass modification, both in terms of ambient temperature and moistening over the Gulf Basin, will occur in wake of frontal passage on Saturday. Northward moisture return beneath the aforementioned EML will probably result in a substantial warm sector by late afternoon Tuesday and into Wednesday farther east. Model run-to-run continuity is such that there is increased confidence in the introduction of 15-percent severe-risk highlights with the expected eastward progression of the trough. Will defer the possibility of an additional area farther east on Thursday until confidence in details related to earlier days becomes more focused. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Thu Feb 22 2024 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Saturday. ...Synopsis... A quiescent upper-air pattern for thunderstorms will exist across the Lower 48 states on Saturday. A mid-level trough over the East will move east into the western Atlantic, while a split flow pattern is forecast with a jet encroaching on southern CA and another speed max moving southward along the British Columbia coast. Surface high pressure will influence conditions across much of the CONUS and a dry/stable airmass will be hostile for thunderstorms. ..Smith.. 02/22/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Thu Feb 22 2024 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Saturday. ...Synopsis... A quiescent upper-air pattern for thunderstorms will exist across the Lower 48 states on Saturday. A mid-level trough over the East will move east into the western Atlantic, while a split flow pattern is forecast with a jet encroaching on southern CA and another speed max moving southward along the British Columbia coast. Surface high pressure will influence conditions across much of the CONUS and a dry/stable airmass will be hostile for thunderstorms. ..Smith.. 02/22/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Thu Feb 22 2024 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Saturday. ...Synopsis... A quiescent upper-air pattern for thunderstorms will exist across the Lower 48 states on Saturday. A mid-level trough over the East will move east into the western Atlantic, while a split flow pattern is forecast with a jet encroaching on southern CA and another speed max moving southward along the British Columbia coast. Surface high pressure will influence conditions across much of the CONUS and a dry/stable airmass will be hostile for thunderstorms. ..Smith.. 02/22/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Thu Feb 22 2024 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Saturday. ...Synopsis... A quiescent upper-air pattern for thunderstorms will exist across the Lower 48 states on Saturday. A mid-level trough over the East will move east into the western Atlantic, while a split flow pattern is forecast with a jet encroaching on southern CA and another speed max moving southward along the British Columbia coast. Surface high pressure will influence conditions across much of the CONUS and a dry/stable airmass will be hostile for thunderstorms. ..Smith.. 02/22/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Thu Feb 22 2024 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Saturday. ...Synopsis... A quiescent upper-air pattern for thunderstorms will exist across the Lower 48 states on Saturday. A mid-level trough over the East will move east into the western Atlantic, while a split flow pattern is forecast with a jet encroaching on southern CA and another speed max moving southward along the British Columbia coast. Surface high pressure will influence conditions across much of the CONUS and a dry/stable airmass will be hostile for thunderstorms. ..Smith.. 02/22/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...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 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...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 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...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 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...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 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...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 0117 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Limited fire weather concerns are expected for Friday across the country, though localized concerns may emerge across portions of NE, CO, and KS. Surface high pressure will gradually build into the southern Plains through the day Friday as the surface low currently over northern OK (as of 07 UTC Thursday) migrates into the Mid-Atlantic region. However, lower pressure along a trailing cold front across the Midwest/northern Plains will promote 15-20 mph northwesterly gradient winds across the central Plains. Boundary-layer mixing through at least 2 km will facilitate downward transfer of 25-35 mph winds by mid to late afternoon. An influx of cooler air behind a cold front (currently moving southward across eastern CO/western KS) will limit RH reductions to some degree across NE, but warmer/drier conditions across eastern CO and KS may allow for afternoon RH minimums near 20%. Elevated fire weather conditions appear probable from western NE into eastern CO and western KS; however, recent fuel guidance indicates that ERCs across these regions are currently at or below the 50th percentile. This will limit the overall fire weather potential, though fuel trends will continue to be monitored for the need for highlights. ..Moore.. 02/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad mid-level trough situated over the Southeast will slowly pivot east to the coast during the period. A surface low over the Mid-Atlantic states will rapidly move northeast into the western Atlantic, as a cold front sweeps southeast off the Carolina/GA coast during the day and into the FL Peninsula. Showers and perhaps a few thunderstorms may be ongoing during the morning over the Carolinas/GA. Models continue to indicate marginal moistening in the low levels ahead of the front. Forecast soundings show surface dewpoints rising through the 50s over the SC/GA coastal plain but with modest lapse rates. Some heating occurs during the afternoon, but veering and weakening low-level flow lends doubt as to whether additional isolated storm activity will redevelop during the afternoon. Given the likelihood for only weak destabilization, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/22/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Thu Feb 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad mid-level trough situated over the Southeast will slowly pivot east to the coast during the period. A surface low over the Mid-Atlantic states will rapidly move northeast into the western Atlantic, as a cold front sweeps southeast off the Carolina/GA coast during the day and into the FL Peninsula. Showers and perhaps a few thunderstorms may be ongoing during the morning over the Carolinas/GA. Models continue to indicate marginal moistening in the low levels ahead of the front. Forecast soundings show surface dewpoints rising through the 50s over the SC/GA coastal plain but with modest lapse rates. Some heating occurs during the afternoon, but veering and weakening low-level flow lends doubt as to whether additional isolated storm activity will redevelop during the afternoon. Given the likelihood for only weak destabilization, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/22/2024 Read more