MESOSCALE DISCUSSION 0079
   NWS STORM PREDICTION CENTER NORMAN OK
   0628 AM CST THU JAN 18 2007
   
   AREAS AFFECTED...NRN SC AND NC
   
   CONCERNING...FREEZING RAIN 
   
   VALID 181228Z - 181630Z
   
   FREEZING RAIN WILL CONTINUE ACROSS MOST OF NC AND NRN SC THROUGH
   LATE MORNING. ADDITIONAL ICE ACCUMULATION WILL OCCUR WITH A QUARTER
   INCH OF NEW ICE POSSIBLE IN SOME AREAS.
   
   LATEST SFC ANALYSIS SHOWS AN ARCTIC SFC HIGH CENTERED ALONG THE
   COAST OF NEW ENGLAND WITH A RIDGE OF SFC HIGH PRESSURE EXTENDING
   SWWD ALONG THE ATLANTIC SEABOARD. SFC WINDS ARE CURRENTLY FROM THE
   NORTH ACROSS THE CAROLINAS WHICH WILL REINFORCE THE COLD TEMPS IN
   PLACE THIS MORNING. THE FREEZING LINE IS CURRENTLY LOCATED FROM ERN
   NC EXTENDING SWWD INTO SRN SC AND WWD INTO NRN GA. THE 12Z SOUNDING
   FROM CHARLESTON SC AND FORECAST SOUNDINGS ACROSS THE REGION SHOW A
   RELATIVELY THICK WARM LAYER EXTENDING FROM JUST ABOVE THE SFC UP TO
   ABOVE 800 MB. IN THE WARM LAYER...COMPLETE MELTING WILL OCCUR AS
   PRECIPITATION FALLS TO THE GROUND RESULTING IN FREEZING RAIN AT THE
   SFC.
   
   CONCERNING PRECIPITATION COVERAGE...A LARGE AREA OF FREEZING RAIN
   CURRENTLY EXISTS ACROSS THE REGION. THIS IS ASSOCIATED WITH THE
   SUBTROPICAL STREAM OF MID-LEVEL MOISTURE EVIDENT ON WATER VAPOR
   IMAGERY. ALTHOUGH VERY HARD TO RESOLVE ATTM...THERE ARE LIKELY
   SEVERAL LOW-AMPLITUDE SHORTWAVE TROUGHS EMBEDDED IN THE ZONAL FLOW
   OVER THE SERN U.S. THIS ALONG WITH DIVERGENCE IN THE EXIT REGION OF
   AN APPROACHING UPPER-LEVEL JET IS LIKELY ENHANCING PRECIPITATION
   ACROSS THE REGION THIS MORNING. AS THIS FEATURE MOVES EWD...THE
   GREATEST AMOUNTS OF FREEZING RAIN SHOULD SHIFT INTO THE ERN
   CAROLINAS BY LATE MORNING. A CHANGEOVER TO SNOW SHOULD OCCUR IN THE
   WRN PART OF THE MCD AREA AS COLDER AIR ADVECTS INTO THAT AREA.
   ALSO...WARMING SFC TEMPS MAY ALLOW A CHANGEOVER TO RAIN ACROSS THE
   SRN PART OF THE MCD AREA BY MIDDAY.
   
   ..BROYLES.. 01/18/2007
   
   
   ...NOTICE...
   SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
   SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
   TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
   FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.
   
   ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CAE...GSP...
   
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   35668163 36228053 36437851 36337694