Mesoscale Discussion 0061
   NWS Storm Prediction Center Norman OK
   1010 AM CST Wed Jan 30 2019

   Areas affected...Eastern Pennsylvania into southeastern New
   York...New Jersey and adjacent portions of the northern Mid Atlantic
   and southern New England

   Concerning...Heavy snow 

   Valid 301610Z - 302015Z

   SUMMARY...A brief burst of heavy snow, strong wind gusts and reduced
   visibilities may accompany the passage of a cold front this
   afternoon, perhaps affecting much of the Greater New York City
   metropolitan area during the 2-4 PM EST time frame.

   DISCUSSION...The leading edge of stronger lower tropospheric cooling
   (centered around 850 mb...where temps falling from roughly -15 to
   -30C), now surging east of the Allegheny Mountains, is forecast to
   continue eastward into western New England and the northern Mid
   Atlantic region through 20-22Z.  Model forecast soundings suggest
   that is being accompanied by increasing boundary layer
   destabilization supportive of deepening convective development, with
   tops likely to approach 10,000+ feet, particularly across parts of
   eastern Pennsylvania and central/northern New Jersey into
   southeastern New York late this afternoon.

   Frontogenetic forcing appears to be supporting a narrow, but
   sustained, evolving band of convection.  This is likely being aided
   by lift within the exit region of a 110-130 kt cyclonic 500 mb jet
   streak forecast to nose across the northern Mid Atlantic, lower
   Hudson Valley, and southern New England by late this afternoon.

   Given the cold thermodynamic profiles, including a layer supportive
   of large dendritic ice crystal growth, guidance is suggestive that
   the convection may be accompanied by a burst of heavy snow rates
   around or in excess of 1 inch per hour.  It appears this may last
   only 15 to 30 minutes at any one location, but it may be accompanied
   by fairly strong surface wind gusts in excess of 30 kts, and sharply
   reduced visibilities.

   ..Kerr.. 01/30/2019

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

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

   LAT...LON   40187685 41577615 42637568 43557345 42817280 42297262
               41427249 40227382 39647578 39647711 40187685