MESOSCALE DISCUSSION 2523
   NWS STORM PREDICTION CENTER NORMAN OK
   1204 AM CST SUN DEC 04 2005
   
   AREAS AFFECTED...NRN WV/NRN VA/MD/PA/SRN NY/NRN NJ
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION 
   
   VALID 040604Z - 041030Z
   
   POTENTIAL FOR SLEET/FREEZING RAIN AND SOME ICE ACCUMULATION WILL
   EXIST OVERNIGHT FROM NRN WV INTO WRN/CNTRL MD...SRN PA...AND PERHAPS
   FAR NRN VA. FURTHER NORTH...MAINLY LIGHT/MDT SNOW WILL SPREAD EWD
   ACROSS MUCH OF PA AND FAR SRN NY OVERNIGHT.
   
   WATER VAPOR IMAGERY DEPICTS LOW AMPLITUDE IMPULSE PROGRESSING EWD
   ACROSS THE OHIO/TENNESSEE VALLEYS...WITH ASSOCIATED FORCING FOR
   ASCENT AND WARM AIR ADVECTION/MOISTURE TRANSPORT RESULTING IN EWD
   SPREAD OF PRECIPITATION ACROSS OH/WV INTO PA/NRN VA/MD AT THIS TIME.
   ATTRIBUTABLE TO 50-60 KT LOW LEVEL JET /AS SAMPLED BY CHARLESTON WV
   AND STERLING VA WSR-88D VADS/...21Z SREF GUIDANCE/03Z RUC FCST
   SOUNDINGS SUGGEST ELEVATED WARM LAYER WILL BE MAINTAINED ABOVE
   SHALLOW COLD BOUNDARY LAYER. THIS SCENARIO WILL BE SUPPORTIVE OF
   FREEZING RAIN AND/OR SLEET WHERE SUB 32F SFC TEMPS ARE
   MAINTAINED...WHICH IS LIKELY ACROSS SRN PA...AND MUCH OF MD/FAR NRN
   VA PRIMARILY NW OF I-95 AND ALONG/NORTH OF I-66.
   
   FURTHER NORTH...SUFFICIENTLY COLD PROFILES WILL FAVOR LIGHT/MDT SNOW
   AS PREDOMINANT PRECIP TYPE ACROSS THE BULK OF PA INTO SRN NY
   OVERNIGHT. ALTHOUGH SNOW RATES SHOULD GENERALLY BE LESS THAN 1
   IN/HR...CONVECTIVE ENHANCEMENT COULD YIELD LOCALLY HIGHER BURSTS
   MAINLY ACROSS CNTRL/SRN PA. OBSERVATIONAL TRENDS/SHORT TERM MODEL
   GUIDANCE SUGGEST LIGHT/MDT SNOW SHOULD SPREAD EWD INTO SE NY/NRN NJ
   BY 12Z.
   
   ..GUYER.. 12/04/2005
   
   
   ATTN...WFO...OKX...ALY...PHI...BGM...BUF...CTP...LWX...PBZ...RLX...CLE...
   
   42437502 42107429 41277422 40727454 40387505 39577628
   38877714 38587875 38297997 38608044 39478084 41588037
   42307898