Aggregator

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 AM CST Tue Jan 21 2025 Valid 211300Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. A large surface high dominates the weather across the CONUS today, with cold, dry, and stable conditions preventing thunderstorms. A strengthening surface low off the Gulf coast may provide isolated thunderstorms offshore later today and tonight, but lightning activity is expected to remain well south of the coast. ..Hart/Wendt.. 01/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 AM CST Tue Jan 21 2025 Valid 211300Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. A large surface high dominates the weather across the CONUS today, with cold, dry, and stable conditions preventing thunderstorms. A strengthening surface low off the Gulf coast may provide isolated thunderstorms offshore later today and tonight, but lightning activity is expected to remain well south of the coast. ..Hart/Wendt.. 01/21/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 AM CST Tue Jan 21 2025 Valid 211300Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. A large surface high dominates the weather across the CONUS today, with cold, dry, and stable conditions preventing thunderstorms. A strengthening surface low off the Gulf coast may provide isolated thunderstorms offshore later today and tonight, but lightning activity is expected to remain well south of the coast. ..Hart/Wendt.. 01/21/2025 Read more

MD 0045 CONCERNING HEAVY SNOW FOR PORTIONS OF FAR WESTERN NEW YORK
Mesoscale Discussion 0045 NWS Storm Prediction Center Norman OK 1030 PM CST Mon Jan 20 2025 Areas affected...portions of far western New York Concerning...Heavy snow Valid 210430Z - 211030Z SUMMARY...At least 2-3 inch/hour snowfall rates should continue past sunrise with an intense lake-effect snow band. DISCUSSION...MRMS mosaic and KTYX radar imagery show an intense, steady-state lake-effect snow band persisting across Jefferson and Lewis Counties in far western NY. This snow-band is benefiting from an optimal fetch of moisture off of Lake Ontario, where 8+ C/km 0-3 km lapse rates are in place. As such, convective snowfall within this lake-effect band should persist past sunrise, as shown by the latest high-resolution guidance consensus. Furthermore, given the convective nature of the band, and degree of saturation in the dendritic growth zone, snowfall rates at least in the 2-3 inch/hour range are expected through the remainder of tonight. ..Squitieri.. 01/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BUF... LAT...LON 43977634 44027567 43947519 43697514 43547540 43587581 43617612 43647630 43977634 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0302 AM CST Tue Jan 21 2025 Valid 241200Z - 291200Z ...DISCUSSION... An amplified and progressive upper trough will move quickly from the MS Valley to the East Coast on Friday/D4, with zonal flow developing behind this system. High pressure will follow, maintaining dry offshore winds across the Southeast. Models remain in relatively good agreement with the large-scale pattern through the weekend, depicting a positive-tilt upper trough over the southwestern states. A broad fetch of west/southwest flow aloft is forecast to extend across the southern Plains and into much of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and eastern TX into the lower MS Valley Saturday/D5 Night into Sunday/D6. Given the antecedent cool air at the surface, substantial clouds and precipitation appear likely, reducing overall destabilization and severe potential. Models diverge around Monday/D7, with uncertainly regarding whether another wave will develop into the northern Plains and Great Lakes as disturbances rotate around the large-scale low. To the west, the trough/low over the Southwest may eventually eject east, but timing for this is uncertain as well with low predictability at this time frame. In any case, severe potential is forecast to be low through the period. Read more

MD 0044 CONCERNING HEAVY SNOW FOR PORTIONS OF FAR WESTERN NEW YORK
Mesoscale Discussion 0044 NWS Storm Prediction Center Norman OK 1016 PM CST Mon Jan 20 2025 Areas affected...portions of far western New York Concerning...Heavy snow Valid 210416Z - 210815Z SUMMARY...Heavy lake-effect snow should continue into the early morning hours, with 3 inch/hour intermittent snowfall rates likely. DISCUSSION...The lake-effect snow-band has taken a more southwest-to-northeast orientation over the past hour or so, with heavy snow recently reported as far south as the Dunkirk Airport. 04Z mesoanalysis shows increased boundary-layer convergence and moistening along a northern Chautaugua to Erie County line, which will support continued heavy snowfall rates within the main band. Snowfall accumulations over very short time periods via reports suggest that near 3 inch/hour snowfall rates may be occurring with this snow band. With the 04Z mesoanalysis showing 7.5 C/km 0-3 km lapse rates present over water (where a long moisture fetch is in place), 2-3 inch/hour snowfall rates may continue into the early morning hours, as also suggested by latest high-resolution guidance consensus. ..Squitieri.. 01/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BUF... LAT...LON 42467965 42677916 42857882 42937844 42827827 42577845 42407890 42337923 42357944 42357954 42467965 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...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 0157 AM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...Synopsis... A surface pressure gradient will persist across southern California, with some strengthening of the gradient likely by late Wednesday afternoon as another in a series of mid-level troughs overspread the Great Basin tomorrow (Wednesday). Another day of offshore flow capable of supporting rapid wildfire spread is expected. By afternoon peak heating, widespread sustained 20-30 mph wind speeds are likely, along with RH dropping to at least the 10-15 percent range. Locally higher wind speeds/gusts are also likely in terrain-favoring areas. Anywhere from the Ventura Valley region to the Laguna Mountains may experience the aforementioned meteorological surface conditions, necessitating the introduction of Critical fire weather highlights this outlook. ..Squitieri.. 01/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more