Storm Prediction Center Mesoscale Discussion 2119

   Mesoscale Discussion 2119
   NWS Storm Prediction Center Norman OK
   0310 PM CDT Thu Sep 26 2024

   Areas affected...portions of eastern Georgia and South Carolina.

   Concerning...Tornado Watch 685...

   Valid 262010Z - 262215Z

   The severe weather threat for Tornado Watch 685 continues.

   SUMMARY...Bands of low-topped storms will continue to move onshore
   through the afternoon and evening. Low-level shear is supportive of
   a tornado risk and will continue to increase tonight.

   DISCUSSION...As of 20 UTC, outer rain bands associated with
   Hurricane Helene were continuing to move onshore across parts of
   eastern GA and SC. Low-level easterly flow is slowly increased
   supporting continued inland advection of a very warm and moist
   tropical air mass. Despite very poor mid-level lapse rates, weak to
   moderate buoyancy continues to support numerous convective elements
   moving onshore within these bands. Strong low-level shear (0-1km SRH
   300-400 m2/s2) is in place and will continue to intensify this
   afternoon and evening as Helene approaches shore. Low-topped
   supercells will continue to pose a tornado risk as they move
   onshore. The risk may be focused near a weak frontal zone where
   low-level shear is enhanced further.

   ..Lyons.. 09/26/2024

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

   ATTN...WFO...ILM...CHS...CAE...JAX...FFC...

   LAT...LON   31718241 33378224 34138157 34428075 34498017 34287961
               33727910 33147903 32138023 30628138 30618162 31038208
               31718241