Mesoscale Discussion 1998
   NWS Storm Prediction Center Norman OK
   0940 PM CST Fri Dec 10 2021

   Areas affected...portions of southern Arkansas into northwest
   Mississippi and western Tennessee

   Concerning...Tornado Watch 552...554...

   Valid 110340Z - 110545Z

   The severe weather threat for Tornado Watch 552, 554 continues.

   SUMMARY...The severe threat continues across Tornado Watches 552 and
   554. All severe hazards remain a concern and a strong tornado is
   possible given the very strong low-level shear in place. Portions of
   Tornado Watch 552 will be replaced by a new Tornado Watch by 05Z.

   DISCUSSION...Multiple linear segments and embedded supercell
   structures persist across southern into eastern AR, with marginally
   severe hail reported in southern AR and a TDS recently observed via
   KNQA radar data across Craighead Counnty, AR. The latest
   mesoanalysis depicts the axis of a strong LLJ roughly along/just
   east of the Mississippi River, which continues to transport deep
   moisture into the TN Valley, as well as foster impressive low-level
   shear. SHV, NQA, and GWX VWPs show relatively long, curved
   hodographs with around 300 m2/s2 0-1 km SRH. As such, at least
   isolated tornadoes remain possible with the more organized storms,
   in addition to damaging gusts and large hail.

   At the moment, there is some uncertainty if a locally higher
   corridor of tornado potential exists and where. However, current
   surface observations across western TN show slightly more backed
   winds compared to points farther west/south, with modest pressure
   falls noted. As such, the greatest chance for an additional isolated
   tornado or two may be across portions of western TN, and a strong
   tornado cannot be ruled out.

   ..Squitieri/Grams.. 12/11/2021

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

   ATTN...WFO...OHX...HUN...PAH...MEG...JAN...LZK...

   LAT...LON   33989332 35389139 36199021 36498866 36558712 36478703
               36238689 35938702 35588721 35098752 34488840 34129016
               33899140 33749249 33989332