Mesoscale Discussion 1161
   NWS Storm Prediction Center Norman OK
   1133 AM CDT Tue Jul 06 2021

   Areas affected...MA...CT...RI...NJ...portions of southern NY and
   eastern PA

   Concerning...Severe potential...Watch likely 

   Valid 061633Z - 061900Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorms are expected to increase in coverage and
   move east-southeast across the area this afternoon.  Damaging winds
   will be the primary threat, with hail also possible with the
   strongest storms.  One or more Severe Thunderstorm Watches will
   likely be required to address the developing risk.

   DISCUSSION...Isolated to widely scattered strong/severe storms have
   developed over western NY as of 16z within an air mass characterized
   by moderate MLCAPE and generally weak (at or below 25 kts) effective
   shear values. Despite the lack of large-scale forcing, additional
   thunderstorm development is anticipated over central portions of NY
   and in the vicinity of a surface trough from the Delaware Valley
   into southern New England as remaining weak MLCIN is removed through
   daytime heating, with multiple multicell clusters moving generally
   east/southeast this afternoon.  A belt of enhanced westerly flow
   averaging 35-40 kts will result in a risk for damaging downburst
   winds with the stronger storms and clusters.  Generally weak
   deep-layer shear and poor mid-level lapse rates will temper the hail
   risk, however a few stronger updrafts may be capable of marginally
   severe hail.

   Given the expected development, one or more Severe Thunderstorm
   Watches is expected by early afternoon.

   ..Bunting/Guyer.. 07/06/2021

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

   ATTN...WFO...GYX...BOX...OKX...ALY...PHI...BGM...BUF...CTP...
   LWX...

   LAT...LON   41687786 42607741 43047427 42637193 42187107 41527111
               40957203 40427336 40127375 39457420 39487512 39747601
               40827728 41687786