Mesoscale Discussion 0758
   NWS Storm Prediction Center Norman OK
   1127 AM CDT Fri May 29 2020

   Areas affected...Northern Mid Atlantic Coast region

   Concerning...Severe potential...Severe Thunderstorm Watch likely 

   Valid 291627Z - 291730Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorms may develop across the Poconos and Catskills
   vicinity as early as the next hour or or so, with a more general
   increase and intensification of thunderstorm during the 3-5 PM EDT
   time frame.  With strongest storms expected to pose at least a risk
   for severe wind and hail, one or more severe weather watches seems
   probable.

   DISCUSSION...Insolation within a seasonably moist boundary layer
   (surface dew points around/above 70F) is contributing to moderately
   large CAPE on the order of 1000-2000+ J/kg, within deepening surface
   troughing to the lee of the Appalachians.  Mid-level flow remains
   broadly anticyclonic, however deepening convective development is
   underway aided by orography, particularly across the Poconos into
   Catskills vicinity.  

   As a short wave trough accelerates northeast of the middle Ohio
   Valley/central Appalachians region, mid-level flow appears likely to
   trend increasingly cyclonic across northern Virginia through eastern
   New York state.  This should contribute to an environment
   increasingly conducive to thunderstorm initiation and
   intensification.  A coinciding strengthening of southwesterly
   mid-level flow (30-50 kt around 500 mb), will provide sufficient
   shear for organizing lines and clusters of storms, with isolated
   discrete supercells also possible.  At least some of this activity
   will pose a risk for large hail, potentially damaging wind gusts,
   and perhaps a tornado or two.

   ..Kerr/Grams.. 05/29/2020

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

   ATTN...WFO...OKX...ALY...PHI...BGM...AKQ...CTP...LWX...

   LAT...LON   41287674 42457524 42457371 40907411 38547674 38017771
               38117908 38917914 41287674