National Weather Service United States Department of Commerce

Turning Stormy in the Northwest

An active fall storm pattern developing in the Pacific Northwest this week will bring areas of heavy rain and high elevation snow. Northern California will benefit from rainfall this week that will aid firefighters given the recent large wildfires. Read More >

Day 1 Convective Outlook issued at 0107 UTC 16 March 2008
SPC AC 160107
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0807 PM CDT SAT MAR 15 2008
   
   VALID 160100Z - 161200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS FOR PARTS OF S CNTRL AND SERN GA
   INTO EXTREME SERN SC...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM S CNTRL AND SE GA INTO SE
   SC AND ERN NC...
   
   ...E CNTRL AND SE GA THROUGH THE ERN CAROLINAS...
   
   PRIMARY SEVERE THREAT EXISTS WITH BAND OF TRAINING SUPERCELLS FROM E
   CNTRL AND SE GA THROUGH EXTREME SERN SC WITHIN LOW LEVEL CONFLUENT
   FLOW REGIME. RECENT CHARLESTON VWP SHOWS DEEP SHEAR OF 70+ KT AND
   VERY LARGE LOW LEVEL HODOGRAPHS WITH 0-1 KM STORM RELATIVE HELICITY
   FROM 300-400 M2/S2. ACTIVITY WILL CONTINUE TO SHIFT ESEWD WITH THE
   THREAT FOR VERY LARGE HAIL AND A FEW TORNADOES NEXT 2-3 HOURS BEFORE
   EVENTUALLY WEAKENING AND MOVING OFFSHORE. SWD EXTENT OF DEVELOPMENT
   WILL BE LIMITED BY STRENGTHENING CONVECTIVE INHIBITION WITH ONSET OF
   NOCTURNAL COOLING AND TENDENCY FOR DEEP LAYER FORCING TO GRADUALLY
   DECREASE AS SHORTWAVE TROUGH AND ATTENDANT LOW LEVEL JET MOVE
   DOWNSTREAM OF THIS REGION.
   
   FARTHER NORTH A MESOSCALE VORTICITY CENTER CONTINUES THROUGH ERN NC.
    CONVECTION EMBEDDED WITHIN WIDESPREAD STRATIFORM RAIN IS DEVELOPING
   WITHIN ZONE OF ASCENT IN ADVANCE OF THIS FEATURE. TEMPERATURES AND
   DEWPOINTS MOSTLY IN THE 50S IN CONJUNCTION WITH WIDESPREAD CLOUDS
   AND RAIN HAVE LIMITED INSTABILITY IN THIS AREA WITH MUCAPE AOB 300
   J/KG. THE LOW LEVEL JET IS SHIFTING NEWD THROUGH ERN NC CONTRIBUTING
   TO LARGE 0-1 KM HODOGRAPHS SUPPORTIVE OF SUPERCELLS AND TORNADOES.
   HOWEVER...RUC SOUNDINGS FOR NERN NC BASED ON OBSERVED TEMPERATURES
   AND DEWPOINTS SUGGEST MOST OF THE CONVECTION WILL REMAIN AT LEAST
   SLIGHTLY ELEVATED. THIS ALONG WITH WEAK INSTABILITY SHOULD SERVE AS
   AN OVERALL LIMITING FACTOR FOR A MORE ROBUST SEVERE THREAT.
   
   ...W CNTRL CA...
   
   STEEP MID LEVEL LAPSE RATES AND COLD MID LEVEL TEMPERATURES
   ATTENDING VORT MAX DROPPING SWD THROUGH CA WILL CONTRIBUTE TO A
   THREAT FOR MARGINALLY SEVERE HAIL NEXT FEW HOURS. STEEP LOW LEVEL
   LAPSE RATES WITH 20+ DEGREE BOUNDARY LAYER TEMPERATURE-DEWPOINTS
   SPREADS MAY ALSO SUPPORT A THREAT FOR ISOLATED STRONG WIND GUSTS
   WITH THE MORE INTENSE CORES. ACTIVITY SHOULD WEAKEN AFTER SUNSET.
   
   ..DIAL.. 03/16/2008
   
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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z