Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1245 AM CST Sun Feb 09 2025 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... Large-scale fire weather conditions are not expected across the contiguous United States (CONUS) on Sunday. Much of the CONUS will be on the downstream side of a positively tilted long-wave trough across North America. This will result in fast zonal mid-level flow across much of the CONUS. However, this strong mid-level flow should be removed from the dry regions of the Southwest. The absence of mid-level support will allow surface winds to remain below criteria thresholds where relative humidity falls into the teens. ..Marsh.. 02/09/2025 ...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 1245 AM CST Sun Feb 09 2025 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... Large-scale fire weather conditions are not expected across the contiguous United States (CONUS) on Sunday. Much of the CONUS will be on the downstream side of a positively tilted long-wave trough across North America. This will result in fast zonal mid-level flow across much of the CONUS. However, this strong mid-level flow should be removed from the dry regions of the Southwest. The absence of mid-level support will allow surface winds to remain below criteria thresholds where relative humidity falls into the teens. ..Marsh.. 02/09/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0079 CONCERNING HEAVY SNOW FOR PARTS OF NEW ENGLAND AND EASTERN NY
Mesoscale Discussion 0079 NWS Storm Prediction Center Norman OK 0901 PM CST Sat Feb 08 2025 Areas affected...parts of New England and eastern NY Concerning...Heavy snow Valid 090301Z - 090700Z SUMMARY...Multiple bands of heavy snow with rates of 1-2 inches per hour should persist into the early morning across eastern New York into parts of New England. DISCUSSION...Radar imagery and surface observations, along with recent reports, indicate multiple swaths of heavy snow are ongoing across parts of the Northeast. The most probable area for the highest rates should exist over southern New England, just to the east-northeast of the occluding transition zone between snow and sleet. OKX dual-pol radar has sampled enhanced KDP below the dendritic growth zone, indicative of heavy snow. 21Z SREF and 00Z HREF guidance support potential for 2 in/hr bursts across parts of CT/MA/RI, until enough warming near 700 mb occurs for sleet and/or mid-level drying advects into the dendritic growth layer during the early morning. Farther north, a more west/east-oriented deformation zone from Lake Ontario to the Capital District should pivot east during the next several hours. Snowfall rates in this band should more steadily hold around 1 in/hr as it spreads across southern parts of VT/NH/ME. ..Grams.. 02/09/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...BTV...OKX...ALY... LAT...LON 43756998 42667047 41946973 41196992 40967253 41477340 41877393 42907461 43477457 43717386 43907156 43756998 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Sun Feb 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Edwards Plateau into central and northeast Texas late Monday night. Severe weather potential is low. ...Synopsis... Zonal flow east of the Divide will generally shift eastward Monday. A low-amplitude shortwave trough will lift northeastward through northern Mexico into West/Central Texas by Tuesday morning. At the surface, a cold front initially near the Gulf Coast will likely move slowly northward in response to the approaching trough. Modest mid-level ascent and weak low-level warm advection will occur late in the period from the Edwards Plateau into northeast Texas. As scattered showers develop overnight Monday, a few embedded thunderstorms may occur given the weak elevated buoyancy present. Though shear will be strong, the poor thermodynamic environment will keep potential for severe weather quite low. ..Wendt.. 02/09/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Sun Feb 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Edwards Plateau into central and northeast Texas late Monday night. Severe weather potential is low. ...Synopsis... Zonal flow east of the Divide will generally shift eastward Monday. A low-amplitude shortwave trough will lift northeastward through northern Mexico into West/Central Texas by Tuesday morning. At the surface, a cold front initially near the Gulf Coast will likely move slowly northward in response to the approaching trough. Modest mid-level ascent and weak low-level warm advection will occur late in the period from the Edwards Plateau into northeast Texas. As scattered showers develop overnight Monday, a few embedded thunderstorms may occur given the weak elevated buoyancy present. Though shear will be strong, the poor thermodynamic environment will keep potential for severe weather quite low. ..Wendt.. 02/09/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Sun Feb 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Edwards Plateau into central and northeast Texas late Monday night. Severe weather potential is low. ...Synopsis... Zonal flow east of the Divide will generally shift eastward Monday. A low-amplitude shortwave trough will lift northeastward through northern Mexico into West/Central Texas by Tuesday morning. At the surface, a cold front initially near the Gulf Coast will likely move slowly northward in response to the approaching trough. Modest mid-level ascent and weak low-level warm advection will occur late in the period from the Edwards Plateau into northeast Texas. As scattered showers develop overnight Monday, a few embedded thunderstorms may occur given the weak elevated buoyancy present. Though shear will be strong, the poor thermodynamic environment will keep potential for severe weather quite low. ..Wendt.. 02/09/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Sun Feb 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Edwards Plateau into central and northeast Texas late Monday night. Severe weather potential is low. ...Synopsis... Zonal flow east of the Divide will generally shift eastward Monday. A low-amplitude shortwave trough will lift northeastward through northern Mexico into West/Central Texas by Tuesday morning. At the surface, a cold front initially near the Gulf Coast will likely move slowly northward in response to the approaching trough. Modest mid-level ascent and weak low-level warm advection will occur late in the period from the Edwards Plateau into northeast Texas. As scattered showers develop overnight Monday, a few embedded thunderstorms may occur given the weak elevated buoyancy present. Though shear will be strong, the poor thermodynamic environment will keep potential for severe weather quite low. ..Wendt.. 02/09/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CST Sun Feb 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Edwards Plateau into central and northeast Texas late Monday night. Severe weather potential is low. ...Synopsis... Zonal flow east of the Divide will generally shift eastward Monday. A low-amplitude shortwave trough will lift northeastward through northern Mexico into West/Central Texas by Tuesday morning. At the surface, a cold front initially near the Gulf Coast will likely move slowly northward in response to the approaching trough. Modest mid-level ascent and weak low-level warm advection will occur late in the period from the Edwards Plateau into northeast Texas. As scattered showers develop overnight Monday, a few embedded thunderstorms may occur given the weak elevated buoyancy present. Though shear will be strong, the poor thermodynamic environment will keep potential for severe weather quite low. ..Wendt.. 02/09/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1134 PM CST Sat Feb 08 2025 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A low risk for a few thunderstorms exists early in the period across the Mid-South region. ...Mid-South Region... Negligible height changes will be noted across lower latitudes today as stronger westerly flow is expected across the Ohio Valley/middle Atlantic region. This flow regime has allowed significant continental air mass to settle into the middle of the country, forcing a cold front to extend across the Carolinas-central Gulf States-central TX early in the period. Latest water-vapor imagery suggests a very weak disturbance is lifting northeast across southwest TX, and this may encourage somewhat stronger flow at 850mb by daybreak from northeast TX into southern AR. Forecast NAM soundings for this region exhibit adequate MUCAPE (in excess of 500 J/kg) if lifting parcels around 1-2km. While large-scale ascent should prove minimal, weak low-level warm advection, and moist uninhibited parcels, suggest isolated convection may evolve along a corridor from southeast OK/northeast TX into southern AR early in the period. This activity will spread east toward northern MS, then weaken as it encounters less favorable environment for deep updrafts. Even so, overall thunder probabilities are generally expected to remain around 10 percent. ..Darrow/Marsh.. 02/09/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1134 PM CST Sat Feb 08 2025 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A low risk for a few thunderstorms exists early in the period across the Mid-South region. ...Mid-South Region... Negligible height changes will be noted across lower latitudes today as stronger westerly flow is expected across the Ohio Valley/middle Atlantic region. This flow regime has allowed significant continental air mass to settle into the middle of the country, forcing a cold front to extend across the Carolinas-central Gulf States-central TX early in the period. Latest water-vapor imagery suggests a very weak disturbance is lifting northeast across southwest TX, and this may encourage somewhat stronger flow at 850mb by daybreak from northeast TX into southern AR. Forecast NAM soundings for this region exhibit adequate MUCAPE (in excess of 500 J/kg) if lifting parcels around 1-2km. While large-scale ascent should prove minimal, weak low-level warm advection, and moist uninhibited parcels, suggest isolated convection may evolve along a corridor from southeast OK/northeast TX into southern AR early in the period. This activity will spread east toward northern MS, then weaken as it encounters less favorable environment for deep updrafts. Even so, overall thunder probabilities are generally expected to remain around 10 percent. ..Darrow/Marsh.. 02/09/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1134 PM CST Sat Feb 08 2025 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A low risk for a few thunderstorms exists early in the period across the Mid-South region. ...Mid-South Region... Negligible height changes will be noted across lower latitudes today as stronger westerly flow is expected across the Ohio Valley/middle Atlantic region. This flow regime has allowed significant continental air mass to settle into the middle of the country, forcing a cold front to extend across the Carolinas-central Gulf States-central TX early in the period. Latest water-vapor imagery suggests a very weak disturbance is lifting northeast across southwest TX, and this may encourage somewhat stronger flow at 850mb by daybreak from northeast TX into southern AR. Forecast NAM soundings for this region exhibit adequate MUCAPE (in excess of 500 J/kg) if lifting parcels around 1-2km. While large-scale ascent should prove minimal, weak low-level warm advection, and moist uninhibited parcels, suggest isolated convection may evolve along a corridor from southeast OK/northeast TX into southern AR early in the period. This activity will spread east toward northern MS, then weaken as it encounters less favorable environment for deep updrafts. Even so, overall thunder probabilities are generally expected to remain around 10 percent. ..Darrow/Marsh.. 02/09/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1134 PM CST Sat Feb 08 2025 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A low risk for a few thunderstorms exists early in the period across the Mid-South region. ...Mid-South Region... Negligible height changes will be noted across lower latitudes today as stronger westerly flow is expected across the Ohio Valley/middle Atlantic region. This flow regime has allowed significant continental air mass to settle into the middle of the country, forcing a cold front to extend across the Carolinas-central Gulf States-central TX early in the period. Latest water-vapor imagery suggests a very weak disturbance is lifting northeast across southwest TX, and this may encourage somewhat stronger flow at 850mb by daybreak from northeast TX into southern AR. Forecast NAM soundings for this region exhibit adequate MUCAPE (in excess of 500 J/kg) if lifting parcels around 1-2km. While large-scale ascent should prove minimal, weak low-level warm advection, and moist uninhibited parcels, suggest isolated convection may evolve along a corridor from southeast OK/northeast TX into southern AR early in the period. This activity will spread east toward northern MS, then weaken as it encounters less favorable environment for deep updrafts. Even so, overall thunder probabilities are generally expected to remain around 10 percent. ..Darrow/Marsh.. 02/09/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1134 PM CST Sat Feb 08 2025 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A low risk for a few thunderstorms exists early in the period across the Mid-South region. ...Mid-South Region... Negligible height changes will be noted across lower latitudes today as stronger westerly flow is expected across the Ohio Valley/middle Atlantic region. This flow regime has allowed significant continental air mass to settle into the middle of the country, forcing a cold front to extend across the Carolinas-central Gulf States-central TX early in the period. Latest water-vapor imagery suggests a very weak disturbance is lifting northeast across southwest TX, and this may encourage somewhat stronger flow at 850mb by daybreak from northeast TX into southern AR. Forecast NAM soundings for this region exhibit adequate MUCAPE (in excess of 500 J/kg) if lifting parcels around 1-2km. While large-scale ascent should prove minimal, weak low-level warm advection, and moist uninhibited parcels, suggest isolated convection may evolve along a corridor from southeast OK/northeast TX into southern AR early in the period. This activity will spread east toward northern MS, then weaken as it encounters less favorable environment for deep updrafts. Even so, overall thunder probabilities are generally expected to remain around 10 percent. ..Darrow/Marsh.. 02/09/2025 Read more

MD 0078 CONCERNING WINTER MIXED PRECIPITATION FOR FAR NORTHERN PORTIONS OF THE MID-ATLANTIC AND FAR SOUTHERN PORTIONS OF NEW ENGLAND
Mesoscale Discussion 0078 NWS Storm Prediction Center Norman OK 0524 PM CST Sat Feb 08 2025 Areas affected...far northern portions of the Mid-Atlantic and far southern portions of New England Concerning...Winter mixed precipitation Valid 082324Z - 090330Z SUMMARY...Snow should overspread the region in the next few hours. With time, the snow should transition to sleet and even freezing rain before ending later this evening/overnight. DISCUSSION...An area of mixed winter precipitation continues across western and central Pennsylvania this evening. This precipitation area developed/is being maintained on the nose of strong low-level warm-air advection across a deep layer. Over the next few hours this warm-air advection and associated isentropic ascent will overspread eastern Pennsylvania and much of New Jersey. Surface temperatures in the upper-20Fs and low-30Fs, coupled with dewpoint temperatures in the upper-teens and low-20Fs, yield wet-bulb temperatures below 32F. Thermal profiles across the region will initially support all snow. However, as the warm-air advection warms the low-levels, the maximum temperature in the column should increase above 32F yielding sleet and potentially eventually freezing rain before precipitation ends from southwest to northeast. ..Marsh.. 02/08/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...PHI...BGM...CTP...LWX... LAT...LON 39177553 39527647 40417671 41247631 41547565 41477463 41017363 39987304 39137378 38907485 39177553 Read more

MD 0077 CONCERNING HEAVY SNOW FOR PARTS OF THE NORTHEAST AND SOUTHERN NEW ENGLAND
Mesoscale Discussion 0077 NWS Storm Prediction Center Norman OK 0521 PM CST Sat Feb 08 2025 Areas affected...parts of the Northeast and southern New England Concerning...Heavy snow Valid 082321Z - 090315Z SUMMARY...Leading corridor of winter storm across the Northeast will produce a heavy snow band before transitioning to sleet/freezing rain from the southwest. Heavy snowfall rates of 1-2 inches per hour are likely. DISCUSSION...A fast-moving swath of winter mixed precip will spread across the Northeast and southern New England states through the rest of this evening. Strengthening low to mid-level ascent will yield a band of heavy snow along the leading periphery of this precip plume where the thermodynamic profile remains entirely below freezing. The initial swath should emanate out of the north-central PA/southwest NY vicinity, where heavy snow has been observed, and should expand east-southeastward along the NY to PA/NJ border area over the next few hours. A longer-lasting deformation zone within the cold-conveyor region should develop east from the Lake Erie vicinity and move across much of southern NY during the next several hours. A highly consistent signal persists across daytime guidance with snowfall rates of 1-2 in/hr. The southern portion of the heavy snow swath to about the Upper DE and Lower Hudson Valleys should mix with/transition to sleet/freezing rain later in the evening. ..Grams.. 02/08/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...OKX...ALY...PHI...BGM...BUF...CTP... LAT...LON 40677327 41357478 41657603 41777768 42117911 42547929 43117880 43417525 43287361 42927212 42647131 42087094 41517107 40927210 40677327 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0636 PM CST Sat Feb 08 2025 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may be noted early this evening. ...01z Update... Low-amplitude short-wave trough is ejecting across the Great Lakes/Ohio Valley region early this evening. Primary corridor for large-scale ascent is now focusing across the upper OH Valley into the northern Middle Atlantic, as LLJ strengthens ahead of the short wave. Widespread precipitation is noted within the warm advection zone but elevated convection is gradually weakening, and only a few flashes of lightning may be noted for the next few hours along the nose of the LLJ. Additionally, shallow weak convection is currently observed along the trailing cold front across KY into TN, but this activity has struggled to attain heights necessary for lightning. This activity will likely remain too shallow the rest of tonight for any meaningful risk for thunderstorms. 01z adjustments will reflect lower confidence in lightning, thus severe probabilities will be removed. ..Darrow.. 02/09/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0636 PM CST Sat Feb 08 2025 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may be noted early this evening. ...01z Update... Low-amplitude short-wave trough is ejecting across the Great Lakes/Ohio Valley region early this evening. Primary corridor for large-scale ascent is now focusing across the upper OH Valley into the northern Middle Atlantic, as LLJ strengthens ahead of the short wave. Widespread precipitation is noted within the warm advection zone but elevated convection is gradually weakening, and only a few flashes of lightning may be noted for the next few hours along the nose of the LLJ. Additionally, shallow weak convection is currently observed along the trailing cold front across KY into TN, but this activity has struggled to attain heights necessary for lightning. This activity will likely remain too shallow the rest of tonight for any meaningful risk for thunderstorms. 01z adjustments will reflect lower confidence in lightning, thus severe probabilities will be removed. ..Darrow.. 02/09/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0636 PM CST Sat Feb 08 2025 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may be noted early this evening. ...01z Update... Low-amplitude short-wave trough is ejecting across the Great Lakes/Ohio Valley region early this evening. Primary corridor for large-scale ascent is now focusing across the upper OH Valley into the northern Middle Atlantic, as LLJ strengthens ahead of the short wave. Widespread precipitation is noted within the warm advection zone but elevated convection is gradually weakening, and only a few flashes of lightning may be noted for the next few hours along the nose of the LLJ. Additionally, shallow weak convection is currently observed along the trailing cold front across KY into TN, but this activity has struggled to attain heights necessary for lightning. This activity will likely remain too shallow the rest of tonight for any meaningful risk for thunderstorms. 01z adjustments will reflect lower confidence in lightning, thus severe probabilities will be removed. ..Darrow.. 02/09/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0636 PM CST Sat Feb 08 2025 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may be noted early this evening. ...01z Update... Low-amplitude short-wave trough is ejecting across the Great Lakes/Ohio Valley region early this evening. Primary corridor for large-scale ascent is now focusing across the upper OH Valley into the northern Middle Atlantic, as LLJ strengthens ahead of the short wave. Widespread precipitation is noted within the warm advection zone but elevated convection is gradually weakening, and only a few flashes of lightning may be noted for the next few hours along the nose of the LLJ. Additionally, shallow weak convection is currently observed along the trailing cold front across KY into TN, but this activity has struggled to attain heights necessary for lightning. This activity will likely remain too shallow the rest of tonight for any meaningful risk for thunderstorms. 01z adjustments will reflect lower confidence in lightning, thus severe probabilities will be removed. ..Darrow.. 02/09/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0636 PM CST Sat Feb 08 2025 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may be noted early this evening. ...01z Update... Low-amplitude short-wave trough is ejecting across the Great Lakes/Ohio Valley region early this evening. Primary corridor for large-scale ascent is now focusing across the upper OH Valley into the northern Middle Atlantic, as LLJ strengthens ahead of the short wave. Widespread precipitation is noted within the warm advection zone but elevated convection is gradually weakening, and only a few flashes of lightning may be noted for the next few hours along the nose of the LLJ. Additionally, shallow weak convection is currently observed along the trailing cold front across KY into TN, but this activity has struggled to attain heights necessary for lightning. This activity will likely remain too shallow the rest of tonight for any meaningful risk for thunderstorms. 01z adjustments will reflect lower confidence in lightning, thus severe probabilities will be removed. ..Darrow.. 02/09/2025 Read more