Storm Prediction Center Mesoscale Discussion 1707

   Mesoscale Discussion 1707
   NWS Storm Prediction Center Norman OK
   1101 PM CDT Tue Jul 21 2026

   Areas affected...parts of central and eastern Virginia

   Concerning...Severe Thunderstorm Watch 509...

   Valid 220401Z - 220530Z

   The severe weather threat for Severe Thunderstorm Watch 509
   continues.

   SUMMARY...A localized damaging wind and tornado threat may persist
   into the overnight hours. As such, the watch has been extended until
   05Z.

   DISCUSSION...Satellite and radar data suggest multiple waves of
   forcing for ascent moving through the region, which are supporting
   more isolated storms now emerging from the Blue Ridge and a larger
   complex of storms approaching the Tidewater Region. A warm and very
   moist air mass resides within the inflow to these storms with latest
   objective analysis indicating MLCAPE as high as 1000-2000 J/kg with
   minimal convective inhibition. Moreover, the current KAKQ VWP is
   sampling quite strong low-level shear with 0-1 km SRH of 400-450
   m2/s2. The low-level shear decreases with westward extent, with the
   KFCX indicating a respectable 0-1 km SRH of around 200 m2/s2.

   It remains unclear whether the current storms are truly rooted
   within the moist, unstable boundary layer, or slightly elevated. On
   the condition storms are surface based, the potential exists for a
   couple tornadoes along with locally damaging winds. As such, the
   watch has been extended until 05z.

   ..Mead.. 07/22/2026

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

   ATTN...WFO...AKQ...LWX...RNK...

   LAT...LON   37667956 37977947 38137718 38077626 37677594 37437633
               37377816 37527946 37667956 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH