Storm Prediction Center Mesoscale Discussion 1703

   Mesoscale Discussion 1703
   NWS Storm Prediction Center Norman OK
   0659 PM CDT Tue Jul 21 2026

   Areas affected...southern Kentucky and northern Tennessee

   Concerning...Severe Thunderstorm Watch 508...510...

   Valid 212359Z - 220200Z

   The severe weather threat for Severe Thunderstorm Watch 508, 510
   continues.

   SUMMARY...Severe storms capable of mainly damaging winds and perhaps
   some large hail are expected to continue this evening across the
   discussion area.

   DISCUSSION...Recent radar trends show initially more discrete
   supercells gradually merging into a line across south-central KY,
   potentially signaling a transition to more of a damaging wind
   threat. At least three semi-discrete supercells still precede the
   evolving line near the KY/TN border, where the risk for a brief
   tornado and/or large hail may persist for the next hour or two.

   Latest CAM guidance offers mixed signals on predominant storm mode
   later this evening into tonight across TN. Regardless, it does
   appear that at least isolated occurrences of damaging wind and large
   hail will remain possible.

   Extrapolation of current storm motions suggests that the most
   intense convection will move south of the Severe Thunderstorm Watch
   508 area prior to the 02Z expiration.

   ..Mead.. 07/21/2026

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

   ATTN...WFO...MRX...JKL...LMK...OHX...PAH...MEG...

   LAT...LON   36398860 36728861 37118797 37348642 37358514 37398427
               37498347 37348298 36628340 36078552 36098799 36098847
               36398860 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN