Mesoscale Discussion 0069
   NWS Storm Prediction Center Norman OK
   0532 PM CST Sat Feb 17 2018

   Areas affected...Southeastern Pennsylvania...Northern New
   Jersey...Southern New York...and Western Connecticut

   Concerning...Heavy snow 

   Valid 172332Z - 180330Z

   SUMMARY...Snowfall rates around or in excess of 1 inch per hour are
   possible for the next few hours this evening from southeastern
   Pennsylvania into the New York City vicinity.

   DISCUSSION...An approaching mid/upper-level shortwave trough and
   low-level warm advection are contributing to ascent across the
   region.  As precipitation spreads east-northeastward across the
   area, melting/evaporating hydrometeors will eventually saturate and
   cool the low-level profiles, resulting in snow reaching the ground. 
   The latest high-resolution numerical guidance generally supports
   snowfall rates around or exceeding 1 inch per hour for the next few
   hours, as the system moves rapidly to the east-northeast.

   ..Jirak.. 02/17/2018

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...BOX...OKX...ALY...PHI...BGM...CTP...

   LAT...LON   40407601 41007525 41767390 42007330 41817284 41257290
               40837350 40267456 40027502 39747566 39847600 40407601