MESOSCALE DISCUSSION 0057
   NWS STORM PREDICTION CENTER NORMAN OK
   0633 AM CST MON JAN 28 2013
   
   AREAS AFFECTED...CENTRAL AND ERN PA/PARTS OF WRN AND CENTRAL NY
   
   CONCERNING...FREEZING RAIN 
   
   VALID 281233Z - 281730Z
   
   SUMMARY...LIGHT SNOW IS EXPECTED TO CHANGE TO LIGHT FREEZING RAIN
   FROM WEST TO EAST ACROSS CENTRAL AND ERN PA AND PARTS OF WRN AND
   CENTRAL NY.  THIS CHANGE IN PRECIPITATION TYPE IS EXPECTED TO OCCUR
   FROM MID-LATE MORNING WITH RATES RANGING GENERALLY FROM 0.05-0.1
   INCH PER 3 HR.
   
   DISCUSSION...AT 12Z...REGIONAL RADAR IMAGERY INDICATED PRECIPITATION
   HAD SPREAD EWD ACROSS MUCH OF PA AND FROM WRN INTO PARTS OF CENTRAL
   NY...WITH SURFACE OBSERVATIONS ACROSS CENTRAL/ERN PA INTO CENTRAL NY
   INDICATING MAINLY LIGHT SNOW.  SINCE 09Z...THE WSR-88D IN CENTRAL PA
   SHOWED LOW LEVEL WINDS AROUND 1 KM AGL HAD VEERED TO WLY AND
   STRENGTHENED TO 50 KT. THIS TREND WAS NOTED EARLIER ACROSS WRN PA
   AND MARKED A PRONOUNCED WARMING IN THAT PORTION OF THE LOWER
   TROPOSPHERE ATOP SUB-FREEZING TEMPERATURES AT THE SURFACE.  LOW
   LEVEL WINDS ACROSS THE REST OF THE DISCUSSION AREA WILL VEER TO WLY
   AND STRENGTHEN THROUGH 18Z SUPPORTING WARMING TEMPERATURES/WARM NOSE
   DEVELOPMENT AROUND 850 MB OF +4 TO +6 C...WHILE SURFACE TEMPERATURES
   TEND TO REMAIN BELOW FREEZING. THESE CHANGES IN THE VERTICAL THERMAL
   PROFILE THROUGH THE MORNING WILL SUPPORT THE EXPECTED CHANGE IN
   PRECIP TYPE FROM SNOW TO FREEZING RAIN.
   
   ..PETERS.. 01/28/2013
   
   
   ATTN...WFO...PHI...BGM...BUF...CTP...
   
   LAT...LON   41197512 39947601 39857642 39877701 40207774 40607833
               40877837 41617802 42497846 42897804 43137727 43157577
               42677524 41897514 41197512