Mesoscale Discussion 1568
   NWS Storm Prediction Center Norman OK
   1211 PM CDT Mon Jul 22 2019

   Areas affected...southern New England southwest to northern Virginia

   Concerning...Severe potential...Watch likely 

   Valid 221711Z - 221845Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Severe risk -- mainly in the form of locally damaging
   winds -- will increase over the next new hours across southern New
   England and the mid-Atlantic region.  A severe thunderstorm watch
   will likely be required.

   DISCUSSION...Despite modest lapse rates aloft, daytime heating of a
   moist warm-sector (east of the advancing cold front crossing western
   PA and south of a warm front lying from northern PA to southern New
   England) is allowing gradual airmass destabilization to occur.

   Latest visible imagery continues to reveal cu/cb development, within
   the zone of clearing (per visible imagery) east of the higher
   terrain.

   With continued heating/destabilization, and a gradual increase in
   southwesterly mid-level flow across the region ahead of the
   advancing upper trough, the environment will become increasingly
   supportive of organized storms.  Attendant risk for locally damaging
   winds will accompany stronger multicell/transient supercell storms,
   with this risk expected to become sufficient to warrant WW issuance
   within the next hour.

   ..Goss/Guyer.. 07/22/2019

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

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

   LAT...LON   42027265 41767146 40977189 40377395 39517467 37847631
               37547877 38047943 40407734 41677415 42027265