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SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 AM CST Fri Dec 22 2023 Valid 241200Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential appears low on Sunday. ...Southern Plains to Lower MS Valley... An upper trough will pivot east across the southern Plains toward the Ozarks and Lower MS Valley on Sunday. At the surface, a cold front will develop southeast across the central and southern Plains during the afternoon/evening, with a Pacific front shifting east across central TX early in the day ahead of the synoptic front. A line and/or clusters of thunderstorms will likely be ongoing Sunday morning across parts of Oklahoma into northern/central TX ahead of these surface boundaries. Some uncertainty in the eastward extent of the Pacific front over central TX exists Sunday morning. Instability will be generally weak, limited by surface dewpoints in the 50s to low 60s across central TX. However, vertically veering low-level wind profiles with result in somewhat enlarged and curved hodographs in the 0-3 km layer. A 30-40 kt southerly low-level jet the first few hours of the period will also contribute to 0-1 km SRH around 100-200 m2/s2. This could conditionally support a low-end tornado risk. However, forecast guidance varies considerably in the quality of low-level thermodynamics. Given this uncertainty in the mesoscale environment, coupled with the climatologically unfavorable time of day (approx. 12-15z), low severe probabilities will not be introduced across parts of central TX at this time. Thunderstorm activity will spread east over the ArkLaTex through the day and toward the Lower MS Valley during the evening/overnight hours. While better low-level moisture will be present across these areas ahead of the eastward-advancing cold front, poor lapse rates and weak instability will limit severe potential. ..Leitman.. 12/22/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CST Fri Dec 22 2023 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS SATURDAY AFTERNOON AND EVENING... ...SUMMARY... Isolated severe thunderstorms producing hail are possible across the southern High Plains Saturday afternoon and evening. ...Southern High Plains... A large-scale upper trough will extend from the Canadian Rockies to northern Mexico on Saturday. Within the broader region of upper troughing, a closed low over AZ will weaken as the southern branch of the trough shifts east across the Four Corners and into the central/southern High Plains. Deep-layer southwesterly flow ahead of this feature will overspread the southern Plains, and vertical shear will be favorable for organized convection. Low-level moisture will remain modest, with surface dewpoints generally in the 50s ahead of an eastward-advancing Pacific front from far eastern NM into western TX. This will limit stronger destabilization, especially given a lack of heating due to ongoing showers/thunderstorms Saturday morning an persistent cloudiness. Nevertheless, steep midlevel lapse rates and increasing midlevel moisture will support around 500-750 MLCAPE by late afternoon into the evening hours. Increasing large-scale ascent will foster thunderstorm development along the surface trough/cool front by late afternoon/early evening. Modest instability and favorable vertical shear may be sufficient for a few thunderstorm cores to become deep enough, and sustained for a sufficient amount of time, to support marginally severe hail from late afternoon through the evening. ..Leitman.. 12/22/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CST Fri Dec 22 2023 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS SATURDAY AFTERNOON AND EVENING... ...SUMMARY... Isolated severe thunderstorms producing hail are possible across the southern High Plains Saturday afternoon and evening. ...Southern High Plains... A large-scale upper trough will extend from the Canadian Rockies to northern Mexico on Saturday. Within the broader region of upper troughing, a closed low over AZ will weaken as the southern branch of the trough shifts east across the Four Corners and into the central/southern High Plains. Deep-layer southwesterly flow ahead of this feature will overspread the southern Plains, and vertical shear will be favorable for organized convection. Low-level moisture will remain modest, with surface dewpoints generally in the 50s ahead of an eastward-advancing Pacific front from far eastern NM into western TX. This will limit stronger destabilization, especially given a lack of heating due to ongoing showers/thunderstorms Saturday morning an persistent cloudiness. Nevertheless, steep midlevel lapse rates and increasing midlevel moisture will support around 500-750 MLCAPE by late afternoon into the evening hours. Increasing large-scale ascent will foster thunderstorm development along the surface trough/cool front by late afternoon/early evening. Modest instability and favorable vertical shear may be sufficient for a few thunderstorm cores to become deep enough, and sustained for a sufficient amount of time, to support marginally severe hail from late afternoon through the evening. ..Leitman.. 12/22/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CST Fri Dec 22 2023 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS SATURDAY AFTERNOON AND EVENING... ...SUMMARY... Isolated severe thunderstorms producing hail are possible across the southern High Plains Saturday afternoon and evening. ...Southern High Plains... A large-scale upper trough will extend from the Canadian Rockies to northern Mexico on Saturday. Within the broader region of upper troughing, a closed low over AZ will weaken as the southern branch of the trough shifts east across the Four Corners and into the central/southern High Plains. Deep-layer southwesterly flow ahead of this feature will overspread the southern Plains, and vertical shear will be favorable for organized convection. Low-level moisture will remain modest, with surface dewpoints generally in the 50s ahead of an eastward-advancing Pacific front from far eastern NM into western TX. This will limit stronger destabilization, especially given a lack of heating due to ongoing showers/thunderstorms Saturday morning an persistent cloudiness. Nevertheless, steep midlevel lapse rates and increasing midlevel moisture will support around 500-750 MLCAPE by late afternoon into the evening hours. Increasing large-scale ascent will foster thunderstorm development along the surface trough/cool front by late afternoon/early evening. Modest instability and favorable vertical shear may be sufficient for a few thunderstorm cores to become deep enough, and sustained for a sufficient amount of time, to support marginally severe hail from late afternoon through the evening. ..Leitman.. 12/22/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CST Fri Dec 22 2023 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS SATURDAY AFTERNOON AND EVENING... ...SUMMARY... Isolated severe thunderstorms producing hail are possible across the southern High Plains Saturday afternoon and evening. ...Southern High Plains... A large-scale upper trough will extend from the Canadian Rockies to northern Mexico on Saturday. Within the broader region of upper troughing, a closed low over AZ will weaken as the southern branch of the trough shifts east across the Four Corners and into the central/southern High Plains. Deep-layer southwesterly flow ahead of this feature will overspread the southern Plains, and vertical shear will be favorable for organized convection. Low-level moisture will remain modest, with surface dewpoints generally in the 50s ahead of an eastward-advancing Pacific front from far eastern NM into western TX. This will limit stronger destabilization, especially given a lack of heating due to ongoing showers/thunderstorms Saturday morning an persistent cloudiness. Nevertheless, steep midlevel lapse rates and increasing midlevel moisture will support around 500-750 MLCAPE by late afternoon into the evening hours. Increasing large-scale ascent will foster thunderstorm development along the surface trough/cool front by late afternoon/early evening. Modest instability and favorable vertical shear may be sufficient for a few thunderstorm cores to become deep enough, and sustained for a sufficient amount of time, to support marginally severe hail from late afternoon through the evening. ..Leitman.. 12/22/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1157 PM CST Thu Dec 21 2023 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Some breezy conditions are likely on Saturday across the central Plains and Southwest as a lee cyclone develops. However, significant moisture will also accompany this cyclone with widespread wetting rain expected. Elsewhere, fuels remain moist with cool and/or moist conditions. Therefore, fire-weather conditions remain minimal across the CONUS. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Some breezy conditions are likely on Saturday across the central Plains and Southwest as a lee cyclone develops. However, significant moisture will also accompany this cyclone with widespread wetting rain expected. Elsewhere, fuels remain moist with cool and/or moist conditions. Therefore, fire-weather conditions remain minimal across the CONUS. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Some breezy conditions are likely on Saturday across the central Plains and Southwest as a lee cyclone develops. However, significant moisture will also accompany this cyclone with widespread wetting rain expected. Elsewhere, fuels remain moist with cool and/or moist conditions. Therefore, fire-weather conditions remain minimal across the CONUS. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Some breezy conditions are likely on Saturday across the central Plains and Southwest as a lee cyclone develops. However, significant moisture will also accompany this cyclone with widespread wetting rain expected. Elsewhere, fuels remain moist with cool and/or moist conditions. Therefore, fire-weather conditions remain minimal across the CONUS. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... Fuels remain mostly moist across the CONUS. In addition, cool and/or dry conditions will prevail today across most of the CONUS. Therefore, fire-weather concerns remain minimal. Wetting rain and mountain snow is expected across Arizona today which will further delay any fire-weather concerns across the region despite ongoing long-term drought conditions. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... Fuels remain mostly moist across the CONUS. In addition, cool and/or dry conditions will prevail today across most of the CONUS. Therefore, fire-weather concerns remain minimal. Wetting rain and mountain snow is expected across Arizona today which will further delay any fire-weather concerns across the region despite ongoing long-term drought conditions. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... Fuels remain mostly moist across the CONUS. In addition, cool and/or dry conditions will prevail today across most of the CONUS. Therefore, fire-weather concerns remain minimal. Wetting rain and mountain snow is expected across Arizona today which will further delay any fire-weather concerns across the region despite ongoing long-term drought conditions. ..Bentley.. 12/22/2023 ...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 1157 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... Fuels remain mostly moist across the CONUS. In addition, cool and/or dry conditions will prevail today across most of the CONUS. Therefore, fire-weather concerns remain minimal. Wetting rain and mountain snow is expected across Arizona today which will further delay any fire-weather concerns across the region despite ongoing long-term drought conditions. ..Bentley.. 12/22/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHERN AZ INTO EXTREME SOUTHWEST NM... ...SUMMARY... A few strong storms are possible during the afternoon and evening across parts of southern Arizona into far southwest New Mexico. Isolated hail and gusty winds are expected to be the primary hazards. ...Southwest... A mid/upper-level cyclone initially off the southern CA/Baja coast is forecast to move east-northeastward and eventually evolve into a shortwave trough, as it begins to interact with a northern-stream shortwave trough moving across the Northwest. Precipitation will likely be rather widespread during the morning across parts of Arizona, but some diurnal destabilization will be possible as colder temperatures aloft overspread modest low-level moisture. Two areas of possible strong-storm development are apparent. The first is across southeast AZ along the southern periphery of the early-day precipitation shield, where storms that develop in an area of somewhat stronger instability across northwest Sonora will move northeastward across the international border. While instability will likely remain weak in this region, favorable large-scale ascent and deep-layer shear may support a threat of isolated hail and/or gusty/damaging winds with the strongest storms, especially if a supercell or two can be sustained. The second area of possible strong-storm development will be closer to the ejecting low across southwest AZ. Cold temperatures aloft (at or below -20C at 500 mb) will compensate somewhat for marginal diurnal heating, with MLCAPE possibly increasing to around 500 J/kg. Deep-layer shear will be sufficient for some storm organization, with isolated hail potential, though backing flow aloft near the low may result in a quick evolution to linear or cluster mode. Late in the evening, convection will spread into parts of central/southern NM. While a stronger elevated storm or two will be possible overnight, diminishing instability will likely limit late-night severe potential. ..Dean/Bentley.. 12/22/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHERN AZ INTO EXTREME SOUTHWEST NM... ...SUMMARY... A few strong storms are possible during the afternoon and evening across parts of southern Arizona into far southwest New Mexico. Isolated hail and gusty winds are expected to be the primary hazards. ...Southwest... A mid/upper-level cyclone initially off the southern CA/Baja coast is forecast to move east-northeastward and eventually evolve into a shortwave trough, as it begins to interact with a northern-stream shortwave trough moving across the Northwest. Precipitation will likely be rather widespread during the morning across parts of Arizona, but some diurnal destabilization will be possible as colder temperatures aloft overspread modest low-level moisture. Two areas of possible strong-storm development are apparent. The first is across southeast AZ along the southern periphery of the early-day precipitation shield, where storms that develop in an area of somewhat stronger instability across northwest Sonora will move northeastward across the international border. While instability will likely remain weak in this region, favorable large-scale ascent and deep-layer shear may support a threat of isolated hail and/or gusty/damaging winds with the strongest storms, especially if a supercell or two can be sustained. The second area of possible strong-storm development will be closer to the ejecting low across southwest AZ. Cold temperatures aloft (at or below -20C at 500 mb) will compensate somewhat for marginal diurnal heating, with MLCAPE possibly increasing to around 500 J/kg. Deep-layer shear will be sufficient for some storm organization, with isolated hail potential, though backing flow aloft near the low may result in a quick evolution to linear or cluster mode. Late in the evening, convection will spread into parts of central/southern NM. While a stronger elevated storm or two will be possible overnight, diminishing instability will likely limit late-night severe potential. ..Dean/Bentley.. 12/22/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHERN AZ INTO EXTREME SOUTHWEST NM... ...SUMMARY... A few strong storms are possible during the afternoon and evening across parts of southern Arizona into far southwest New Mexico. Isolated hail and gusty winds are expected to be the primary hazards. ...Southwest... A mid/upper-level cyclone initially off the southern CA/Baja coast is forecast to move east-northeastward and eventually evolve into a shortwave trough, as it begins to interact with a northern-stream shortwave trough moving across the Northwest. Precipitation will likely be rather widespread during the morning across parts of Arizona, but some diurnal destabilization will be possible as colder temperatures aloft overspread modest low-level moisture. Two areas of possible strong-storm development are apparent. The first is across southeast AZ along the southern periphery of the early-day precipitation shield, where storms that develop in an area of somewhat stronger instability across northwest Sonora will move northeastward across the international border. While instability will likely remain weak in this region, favorable large-scale ascent and deep-layer shear may support a threat of isolated hail and/or gusty/damaging winds with the strongest storms, especially if a supercell or two can be sustained. The second area of possible strong-storm development will be closer to the ejecting low across southwest AZ. Cold temperatures aloft (at or below -20C at 500 mb) will compensate somewhat for marginal diurnal heating, with MLCAPE possibly increasing to around 500 J/kg. Deep-layer shear will be sufficient for some storm organization, with isolated hail potential, though backing flow aloft near the low may result in a quick evolution to linear or cluster mode. Late in the evening, convection will spread into parts of central/southern NM. While a stronger elevated storm or two will be possible overnight, diminishing instability will likely limit late-night severe potential. ..Dean/Bentley.. 12/22/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1152 PM CST Thu Dec 21 2023 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHERN AZ INTO EXTREME SOUTHWEST NM... ...SUMMARY... A few strong storms are possible during the afternoon and evening across parts of southern Arizona into far southwest New Mexico. Isolated hail and gusty winds are expected to be the primary hazards. ...Southwest... A mid/upper-level cyclone initially off the southern CA/Baja coast is forecast to move east-northeastward and eventually evolve into a shortwave trough, as it begins to interact with a northern-stream shortwave trough moving across the Northwest. Precipitation will likely be rather widespread during the morning across parts of Arizona, but some diurnal destabilization will be possible as colder temperatures aloft overspread modest low-level moisture. Two areas of possible strong-storm development are apparent. The first is across southeast AZ along the southern periphery of the early-day precipitation shield, where storms that develop in an area of somewhat stronger instability across northwest Sonora will move northeastward across the international border. While instability will likely remain weak in this region, favorable large-scale ascent and deep-layer shear may support a threat of isolated hail and/or gusty/damaging winds with the strongest storms, especially if a supercell or two can be sustained. The second area of possible strong-storm development will be closer to the ejecting low across southwest AZ. Cold temperatures aloft (at or below -20C at 500 mb) will compensate somewhat for marginal diurnal heating, with MLCAPE possibly increasing to around 500 J/kg. Deep-layer shear will be sufficient for some storm organization, with isolated hail potential, though backing flow aloft near the low may result in a quick evolution to linear or cluster mode. Late in the evening, convection will spread into parts of central/southern NM. While a stronger elevated storm or two will be possible overnight, diminishing instability will likely limit late-night severe potential. ..Dean/Bentley.. 12/22/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0657 PM CST Thu Dec 21 2023 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms remain possible tonight across parts of southern California and Arizona, and also from north Oklahoma into southeast Kansas. Severe thunderstorms are not expected. ...Synopsis... A deep-layer cyclone off of the southern CA/Baja coasts is forecast to move eastward tonight. Most thunderstorm activity will likely remain offshore tonight in closer proximity to the low, but some threat for isolated thunderstorms will continue across near coastal areas of southern CA, and potentially expand into southeast CA/southern AZ overnight. A strong storm or two cannot be ruled out near the coastline, but weak instability should limit the severe-thunderstorm threat. Convection may increase later tonight across parts of northern OK and southern KS, in association with a low-amplitude midlevel shortwave trough moving across the central Plains. While instability will remain weak, sporadic lightning flashes will be possible with the strongest convection. ..Dean.. 12/22/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0657 PM CST Thu Dec 21 2023 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms remain possible tonight across parts of southern California and Arizona, and also from north Oklahoma into southeast Kansas. Severe thunderstorms are not expected. ...Synopsis... A deep-layer cyclone off of the southern CA/Baja coasts is forecast to move eastward tonight. Most thunderstorm activity will likely remain offshore tonight in closer proximity to the low, but some threat for isolated thunderstorms will continue across near coastal areas of southern CA, and potentially expand into southeast CA/southern AZ overnight. A strong storm or two cannot be ruled out near the coastline, but weak instability should limit the severe-thunderstorm threat. Convection may increase later tonight across parts of northern OK and southern KS, in association with a low-amplitude midlevel shortwave trough moving across the central Plains. While instability will remain weak, sporadic lightning flashes will be possible with the strongest convection. ..Dean.. 12/22/2023 Read more

No watches are valid as of Thu Dec 21 22:31:02 UTC 2023.