Mesoscale Discussion 0493
   NWS Storm Prediction Center Norman OK
   0943 PM CDT Sat Apr 19 2025

   Areas affected...portions of southeast Pennsylvania and northeast
   Maryland

   Concerning...Severe potential...Watch unlikely 

   Valid 200243Z - 200415Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Strong to severe gusts will accompany an eastward moving
   MCS over the next few hours.

   DISCUSSION...A rapidly eastward propagating, likely cold-pool-driven
   MCS, with a history of measured severe/damaging gusts (some
   exceeding 65 kts), persists along the PA/MD border. The 00Z observed
   IAD sounding depicts a relatively dry boundary layer in the general
   area, suggesting that deep-layer evaporative cooling is contributing
   to a deep/strong cold pool, which is likely supporting both MCS
   longevity, and severity of the corresponding severe wind swath.
   However, decreasing lightning trends raises questions as to how long
   this MCS will persist given weak to modest synoptic forcing, with
   longevity dependent on cold pool maintenance. Nonetheless, as long
   as the MCS persists, strong to potentially severe gusts remain
   possible.

   ..Squitieri.. 04/20/2025

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

   ATTN...WFO...PHI...CTP...LWX...

   LAT...LON   39447672 39537694 39727698 39947678 39947665 39987619
               39837556 39587542 39377562 39337612 39447672 

   MOST PROBABLE PEAK WIND GUST...65-80 MPH