MESOSCALE DISCUSSION 2265
   NWS STORM PREDICTION CENTER NORMAN OK
   0615 PM CST THU DEC 27 2007
   
   AREAS AFFECTED...TX/OK PANHANDLES/SWRN KS
   
   CONCERNING...HEAVY SNOW 
   
   VALID 280015Z - 280345Z
   
   WIDESPREAD LIGHT SNOW WITH RATES 0.5 TO 1 INCH PER HOUR WILL
   CONTINUE TO DEVELOP THROUGH THE EVENING...WITH CONVECTIVE ELEMENTS
   EXCEEDING 1-2 INCHES PER HOUR.
   
   CURRENT SURFACE ANALYSIS SHOWS LOW CENTER IS JUST SOUTHWEST OF LBB
   AND EXPECTED TO CONTINUE TO MOVE SLOWLY EWD/NEWD...REACHING SPS
   AROUND 06 UTC. LARGE-SCALE ASCENT ASSOCIATED WITH MIDLEVEL VORTICITY
   CENTER/UPPER LEVEL JET MAXIMUM PRESENTLY OVERSPREADING AREA...WHICH
   IS CLEARLY DEPICTED BY LARGE DEVELOPING/COOLING CLOUD SHIELD ON IR
   IMAGERY.  CURRENT RADAR SHOWS AN AREA OF CONVECTION FROM PVW TO
   AMA...AND BASED ON THE LATEST NAM AND SREF THE POTENTIAL FOR UPRIGHT
   OR POSSIBLY SLANTWISE CONVECTION WILL CONTINUE FROM THE PANHANDLES
   TO EXTREME SWRN KS. THE SURFACE TEMPERATURE WILL REMAIN BELOW
   FREEZING AND SNOW RATES ASSOCIATED WITH CONVECTION WILL LOCALLY
   EXCEED 1-2 INCHES PER HOUR. 
   
   FARTHER NEWD LAPSE RATES ARE NOT AS STEEP...BUT SOME BANDING OF THE
   SNOW MAY BE ASSOCIATED WITH WEAK FRONTOGENETICAL FORCING AS THE 850
   LOW CENTER MOVES TO WRN OK BY 06 UTC. GIVEN THE COLD SURFACE
   TEMPERATURES AND DEEP DENDRITIC PROFILE OVER KS /ABOUT 150 MB LAYER
   PER 18 UTC NAM FORECAST SOUNDINGS/...SNOW RATES MAY APPROACH 1 INCH
   PER HOUR LATER THIS EVENING.
   
   ..BRIGHT.. 12/28/2007
   
   
   ...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...ICT...OUN...DDC...LUB...AMA...
   
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   38889850 38929793 38279714 37539730 36519824 35009988
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