Mesoscale Discussion 0440
   NWS Storm Prediction Center Norman OK
   0253 PM CDT Wed Apr 22 2020

   Areas affected...east-central Texas and west-central Louisiana

   Concerning...Tornado Watch 133...

   Valid 221953Z - 222100Z

   The severe weather threat for Tornado Watch 133 continues.

   SUMMARY...Convective trends suggest a recent uptick in intensity
   over the past half hour, with rotation noted in several cells.  All
   modes of severe weather remain possible with this activity.

   DISCUSSION...Storms across north/northeastern portions of WW 133
   have increased in intensity over the past half hour or so - and are
   now exhibiting more supercellular characteristics.  A subtle warm
   front/differential heating zone has developed along an east-west
   axis in vicinity of these storms - generally from near Tyler, TX to
   near Fort Polk, Louisiana.  South of this effective boundary,
   continued low-level advection and limited insolation has maintained
   a moderately unstable airmass, which is likely allowing for storms
   to become more surface-based and ingest vorticity along the weak
   differential heating zone.  This suggests an increase in the tornado
   and hail threat with this convection.  Again, a strong tornado
   cannot be completely ruled out given 500+ m2/s2 effective SRH near
   the differential heating zone.

   As storms migrate northeast, spatial extensions of WW 133 may be
   needed.

   ..Cook.. 04/22/2020

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

   ATTN...WFO...JAN...LCH...SHV...HGX...FWD...

   LAT...LON   32579342 32479421 32199528 31819579 31299576 30989517
               31049433 31069326 31149228 31439199 31949217 32299269
               32579342