Mesoscale Discussion 1253
   NWS Storm Prediction Center Norman OK
   1156 PM CDT Sat Jul 10 2021

   Areas affected...Southern OK...Far Northwest/North-Central TX

   Concerning...Severe Thunderstorm Watch 368...370...

   Valid 110456Z - 110630Z

   The severe weather threat for Severe Thunderstorm Watch 368, 370
   continues.

   SUMMARY...Strong, damaging wind gusts will likely continue for the
   next few hours.

   DISCUSSION...Western portion of the ongoing convective line has
   recently surged more southwestward towards a pocket of greater
   instability. This surge coincided with storm development briefly
   preceding the outflow before it was then overrun by the outflow.
   This merger appears to have allowed the updrafts to become more
   colocated with the outflow, strengthening the overall structure of
   the line and making damaging wind gusts more likely. A 53 kt wind
   gusts was reported about an hour ago in Chickasha. The more
   southwestward storm motion will likely keep this line in Severe
   Thunderstorm Watch 368 past its original expiration time of 0500Z.

   Portion of this line moving through Pontotoc and into John and Coal
   Counties has shown a bit more southeastward motion. KTLX velocity
   data also shows an area stronger outflow, which looks to be related
   to interaction with another outflow boundary from antecedent storms
   to the east. 

   Airmass downstream of this line is moist and unstable, suggesting
   the line should continue for at least the next several hours,
   despite low-level nocturnal stabilization. The more southeastward
   motion of the central portion of the line may result in the need to
   expand Severe Thunderstorm Watch 370 eastward along the Red River in
   TX.

   ..Mosier.. 07/11/2021

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

   ATTN...WFO...TSA...FWD...OUN...

   LAT...LON   34689975 35009919 34759591 34099534 33659592 33579679
               33609779 33699893 33909959 34199984 34689975