MESOSCALE DISCUSSION 0058
   NWS STORM PREDICTION CENTER NORMAN OK
   1055 AM CST MON JAN 28 2013
   
   AREAS AFFECTED...PORTIONS OF ERN NY...NERN PA...NRN/CNTRL
   NJ...CT...RI...WRN/SRN MA
   
   CONCERNING...WINTER MIXED PRECIPITATION 
   
   VALID 281655Z - 282300Z
   
   SUMMARY...SNOW WILL TRANSITION TO FREEZING RAIN THROUGH THE
   AFTERNOON...WITH LIQUID-EQUIVALENT RATES OF 0.03 TO LOCALLY 0.07
   IN/HR ANTICIPATED.
   
   DISCUSSION...MORNING UPPER AIR ANALYSES AND AREA VWP DATA DEPICT THE
   STRONG ELEVATED WARM ADVECTION REGIME MAINTAINING A BROAD AREA OF
   PRECIPITATION FROM THE LOWER GREAT LAKES INTO SRN NEW ENGLAND. THE
   UPSTREAM 12Z PIT RAOB SUGGESTS A MAXIMUM ELEVATED WARM-LAYER TEMP
   AROUND 6C NEAR THE 850-MB LEVEL. AS THE ABOVE-FREEZING WARM LAYER
   CONTINUES ADVANCING ENEWD ATOP SUBFREEZING WET-BULB SFC TEMPS PER
   REGIONAL SFC OBS...DESCENDING HYDROMETEORS WILL BECOME INCREASINGLY
   SUSCEPTIBLE TO MELTING BEFORE REFREEZING ON THE GROUND. AS
   SUCH...ONGOING SNOW WILL TRANSITION TO FREEZING RAIN FROM WSW TO
   ENE...AND A BRIEF PERIOD OF SLEET MAY OCCUR DURING THIS PROCESS.
   FREEZING RAIN RATES AROUND 0.03 IN/HR ARE ANTICIPATED...AND VERY
   MODEST CONVECTIVE ENHANCEMENTS COULD SUPPORT LOCALIZED RATES TO 0.07
   IN/HR. THE FREEZING-RAIN THREAT WILL CONTINUE THROUGHOUT MUCH OF THE
   AFTERNOON BEFORE DECREASING IN COVERAGE/INTENSITY. THE MOST
   PERSISTENT FREEZING RAIN IS EXPECTED FROM NERN PA ENEWD INTO WRN
   MA/CT.
   
   THE ISALLOBARIC RESPONSE TO SFC PRESSURE FALLS ACROSS PARTS OF
   CNTRL/NRN NY AND ADJACENT NEW ENGLAND WILL ALLOW SFC WINDS TO BACK
   OVER LONG ISLAND AND COASTAL SRN NEW ENGLAND. IN THESE AREAS...THE
   INFLUX OF RELATIVELY WARMER...MARINE-MODIFIED AIR MAY ALLOW FREEZING
   RAIN TO BE MORE TRANSIENT/SPOTTY...ESPECIALLY OVER COASTAL AREAS
   AFTER 20Z.
   
   ..COHEN.. 01/28/2013
   
   
   ATTN...WFO...BOX...OKX...ALY...PHI...BGM...BUF...CTP...
   
   LAT...LON   41827157 41247154 40877230 40617338 40117424 40147503
               40637588 41087612 41837598 42257591 42847602 43507616
               43887627 44197615 44277570 43627452 42827329 41827157