Storm Prediction Center Mesoscale Discussion 505

   Mesoscale Discussion 0505
   NWS Storm Prediction Center Norman OK
   0507 PM CDT Sun Apr 20 2025

   Areas affected...Central and Eastern Arkansas

   Concerning...Tornado Watch 154...

   Valid 202207Z - 202300Z

   The severe weather threat for Tornado Watch 154 continues.

   SUMMARY...Thunderstorms will continue east across Arkansas this
   afternoon and evening. The low-level environment will remain
   supportive of tornadoes. A new Tornado Watch will likely be needed
   across eastern Arkansas -- to the east of the existing watch --
   within the hour.

   DISCUSSION...A mixed-mode (linear segments and discrete cells) line
   of thunderstorms continues to move east across Arkansas this
   afternoon. The environment along and ahead of these storms is
   characterized by 100-mb mixed-layer CAPE around 1000 J/kg and
   effective-layer shear around 50-60 knots. Additionally, the Little
   Rock VAD depicts strong low-level curvature with 0-1 km SRH
   averaging around 180-190 m2/s2 over the last hour. Discrete
   thunderstorms moving from southwest Arkansas toward central Arkansas
   have shown increasing organization/mid-level rotation, with
   broadcast media reporting a tornado recently in Garland County. 

   This environment should evolve east across the state this evening,
   supporting a continued tornado threat east of the ongoing tornado
   watch. With Tornado Watch 154 scheduled to expire by 00 UTC / 7 PM
   CDT, a new tornado watch for portions of central and eastern
   Arkansas will likely be needed within the hour.

   ..Marsh/Guyer.. 04/20/2025

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

   ATTN...WFO...MEG...JAN...LZK...SGF...SHV...

   LAT...LON   36309300 36529184 36399031 35858986 34309047 34299051
               33299101 32979137 32899293 33049390 33949373 36309300