MESOSCALE DISCUSSION 0071
   NWS STORM PREDICTION CENTER NORMAN OK
   1045 AM CST TUE FEB 03 2004
   
   AREAS AFFECTED...NERN PA / CNTRL/ERN NY
   
   CONCERNING...PRECIPITATION TRENDS...WINTER PRECIPITATION 
   
   VALID 031645Z - 032245Z
   
   HEAVY SNOW...AT RATES IN EXCESS OF 1 INCH/HOUR ARE EXPECTED TO
   DEVELOP THIS AFTERNOON OVER PORTIONS OF CNTRL AND ERN NY...PRIMARILY
   N AND W OF A LINE FROM 20NW OF MSV TO 15W OF RUT. A NARROW AXIS OF
   FREEZING RAIN WITH RATES APPROACHING 0.05 TO 0.10 INCH/HOUR WILL BE
   MOST LIKELY S AND E OF THIS LINE...OVER PARTS OF NERN PA/SERN NY AND
   POSSIBLY FAR NWRN NJ.
   
   AS OF 16Z...WATER VAPOR IMAGERY INDICATED A VIGOROUS...
   NEGATIVELY-TITLED MID-LEVEL TROUGH LIFTING NEWD THROUGH THE MIDDLE
   ATLANTIC STATES. STRONG DYNAMIC FORCING AHEAD OF THIS FEATURE HAS
   RESULTED IN A FAIRLY WIDESPREAD PRECIPITATION SHIELD THIS MORNING
   FROM WV/DELMARVA REGION NWD ACROSS MUCH OF PA AND WRN NY. INTENSE
   WAA REGIME IN PLACE FROM ERN VA NWD INTO SERN PA /PER LOCAL VWPS AND
   RUC DIAGNOSTIC FIELDS/ IS LIKELY RESPONSIBLE FOR THE HIGHER
   REFLECTIVITY VALUES AND A NARROW SWATH OF FREEZING RAIN IN ERN/SERN
   QUADRANT OF LARGER PRECIPITATION SHIELD.
   
   AS MID-LEVEL TROUGH CONTINUES TO LIFT NEWD THROUGH THE DISCUSSION
   AREA THIS AFTERNOON...EXPECT ASSOCIATED LLJ AXIS TO CONCURRENTLY
   SHIFT NWD...WITH LOW-LEVEL MOIST/THERMAL ADVECTION BECOMING
   MAXIMIZED ACROSS NERN PA AND ERN NY. THESE PROCESSES SHOULD
   CONTRIBUTE TO DEVELOPING WARM NOSE ABOVE SUBFREEZING BOUNDARY-LAYER
   WITH AXIS OF FREEZING RAIN...CURRENTLY FROM FAR NRN VA NEWD INTO
   SERN PA /NEAR CXY/...SLOWLY DEVELOPING NEWD ACROSS PORTIONS OF NERN
   PA AND SERN NY...TO THE NW OF FREEZING LINE THAT EXTENDED FROM ABE
   NEWD TO N OF NYC AS OF 16Z.
   
   FARTHER TO THE NW...PRIMARILY HEAVY SNOW IS EXPECTED NW OF A MSV TO
   RUT LINE. HERE...DEEP-LAYER UPWARD VERTICAL MOTION ASSOCIATED WITH
   MID-LEVEL DEFORMATION AXIS WILL RESULT IN SATURATED THERMODYNAMIC
   PROFILES THROUGH TEMPERATURE RANGE FAVORING DENDRITIC GROWTH. HOURLY
   SNOWFALL RATES OF 1 INCH/PER HOUR WILL BE COMMON WITH SOME LOCALIZED
   RATES APPROACHING 2 INCHES/HOUR.
   
   ..MEAD.. 02/03/2004
   
   
   ATTN...WFO...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
   
   41307661 42247682 43127629 43837546 44357462 43987351
   42047322 40847442 40747539