Storm Prediction Center Mesoscale Discussion 330

   Mesoscale Discussion 0330
   NWS Storm Prediction Center Norman OK
   0233 PM CDT Mon Mar 31 2025

   Areas affected...Northern Virginia into central Maryland...southeast
   Pennsylvania...and northwest New Jersey

   Concerning...Severe potential...Watch possible 

   Valid 311933Z - 312130Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorm development is expected within the next
   couple of hours across parts of the Mid-Atlantic region. The
   convective environment should support a damaging wind threat into
   the evening hours. Trends will be monitored for possible watch
   issuance.

   DISCUSSION...Over the past few hours, GOES visible imagery has shown
   a gradual increase in agitated cumulus within a deepening trough
   axis in the lee of the central Appalachians. Steady diurnal heating
   under broken cloud cover has allowed temperatures to warm into the
   upper 70s to low 80s - a few degrees warmer than anticipated by
   recent guidance, which suggests that thunderstorm initiation should
   become increasingly probable in the next couple of hours. Buoyancy
   on the northern periphery of returning moisture appears to be meager
   due to somewhat poor mid-level lapse rates and overall low quality
   moisture. This will modulate updraft intensities to some degree, but
   strong speed shear noted in upstream VWPs should help promote
   longevity of initially semi-discrete cells. Mean wind and deep-layer
   shear vectors oriented along the lee trough axis will likely promote
   upscale growth with time and perhaps an increasing damaging wind
   threat as cold pools amalgamate within an environment featuring
   low-level lapse rates between 7-8 C/km. Convective trends will
   continue to be monitored, and watch issuance is possible if/when
   thunderstorm development becomes more imminent and storm coverage
   becomes sufficient for a more widespread threat across the region.

   ..Moore/Smith.. 03/31/2025

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

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

   LAT...LON   39367618 38907719 38397825 38347865 38507884 38687899
               38917900 39237878 39507844 39777794 41307567 41467502
               41267454 40897427 40457437 39967509 39367618 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN