Mesoscale Discussion 1269
   NWS Storm Prediction Center Norman OK
   1148 AM CDT Tue Jul 13 2021

   Areas affected...Portions of the Northeast

   Concerning...Severe potential...Watch likely 

   Valid 131648Z - 131815Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Scattered storms developing will pose a risk for damaging
   winds and severe hail this afternoon/evening. A severe thunderstorm
   watch will likely be issued in the next hour.

   DISCUSSION...Visible satellite shows morning clearing has given way
   to widespread cumulus development across the region. Surface
   temperatures have warmed into the low to mid 80s F amid rich
   low-level moisture characterized by dew point temperatures in the
   low to mid 70s F. This has led to rapid destabilization, with MLCAPE
   values of 1500 J/kg being analyzed across the region, and
   approaching 2000-2500 J/kg across portions of south-central
   Pennsylvania. Isolated storms are already beginning to develop, with
   a severe/maturing convective cell noted in central New York. 

   This trend is expected to continue, with scattered storms expected
   across the region by early to mid afternoon. With effective bulk
   shear of 35-40 kt, storms should organize into a mixture of
   multicells and supercells, posing a risk for mainly damaging winds
   and some severe hail, and a tornado or two is possible. Given these
   trends, a severe thunderstorm watch will likely be needed for the
   region in the next hour or so.

   ..Karstens/Dial.. 07/13/2021

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

   ATTN...WFO...BTV...ALY...PHI...BGM...BUF...CTP...PBZ...

   LAT...LON   40077851 40317946 42157955 43467877 43467709 44027622
               44237541 43817479 41887524 40777511 40097610 39967680
               40077851