Storm Prediction Center Mesoscale Discussion 707

   Mesoscale Discussion 0707
   NWS Storm Prediction Center Norman OK
   0711 PM CDT Mon May 05 2025

   Areas affected...Parts of the Mid-Atlantic to the central
   Appalachians

   Concerning...Severe Thunderstorm Watch 228...

   Valid 060011Z - 060215Z

   The severe weather threat for Severe Thunderstorm Watch 228
   continues.

   SUMMARY...A band of thunderstorms may continue to pose a severe
   hail/wind risk through the mid-evening hours across northern
   Virginia and Maryland into southwest Pennsylvania. Downstream watch
   issuance is not likely due to the expectation of a gradually waning
   thermodynamic environment.

   DISCUSSION...An arcing band of thunderstorms has begun to develop
   from southwest PA into northern VA, and is largely being driven by
   strong ascent ahead of an approaching mid-level shortwave/vorticity
   maximum (evident in water-vapor imagery). Downstream from this band,
   the 00 UTC PBZ sounding sampled a weakly capped environment (MLCIN
   of around -50 J/kg) and some residual buoyancy.  Recent RAP
   mesoanalysis estimates align well with these observations and show a
   narrow warm sector extending from southwest PA into parts of the
   Mid-Atlantic where strong/severe thunderstorm clusters continue. A
   strongly sheared kinematic environment was also noted with weak
   easterly low-level flow beneath 30-40 knot southeasterly mid-level
   flow supporting an elongated hodograph. The combination of favorable
   ascent and strong shear may compensate for the modest thermodynamic
   environment and support a few organized cells capable of severe hail
   (most likely between 1.0 to 1.5 inches) and damaging gusts for the
   next few hours. With time, the onset of nocturnal cooling should
   steadily inhibit surface-based convection and begin reducing the
   overall severe threat. As such, downstream watch issuance from 228
   is not anticipated.

   ..Moore.. 05/06/2025

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

   ATTN...WFO...CTP...LWX...PBZ...

   LAT...LON   39817715 39557704 39297703 39057707 38827724 38707759
               38817794 39337897 39878015 40078069 40368076 40698058
               40958014 41047963 40957903 40687841 40387781 40037735
               39817715 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN