Mesoscale Discussion 1001
   NWS Storm Prediction Center Norman OK
   0753 PM CDT Fri Jun 18 2021

   Areas affected...southern portions of IN/OH...northern KY

   Concerning...Tornado Watch 279...280...

   Valid 190053Z - 190200Z

   The severe weather threat for Tornado Watch 279, 280 continues.

   SUMMARY...The severe weather threat continues with Tornado Watch 279
   and Severe Thunderstorm Watch 280.  A downstream watch may be needed
   south/southeast of existing watches prior to 02z.

   DISCUSSION...Several supercell thunderstorms continue within WW
   279/280 at 0030z, with strengthening storms also noted near the
   IL/IN border near Sullivan, IN.  Very large hail, isolated damaging
   winds, and at least one tornado have been reported with these
   intense storms.  Gradual upscale growth is anticipated over the next
   few hours as warm advection strengthens and promotes increasing
   storm coverage.  Linear bowing segments are likely to evolve with
   time and continue moving east/southeast across locally extended
   portions of WW 279/280 and potentially requiring issuance of one or
   more downstream watches prior to 02z.  Increasing MLCIN with
   southward extent casts some uncertainty on the extent of the severe
   risk, however damaging winds, possibly significant, will become an
   increasingly prominent risk over the next few hours.  Severe hail
   will remain possible with persistent supercell structures. Some
   tornado risk will also continue with both supercell and bowing
   segments given background environment low-level SRH of 200-250
   m2/s2. 

   Observational trends will continue to be monitored for the potential
   for additional watch issuance.

   ..Bunting/Guyer.. 06/19/2021

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

   ATTN...WFO...RLX...JKL...ILN...LMK...IND...PAH...ILX...

   LAT...LON   39298662 39748545 39918464 39848405 39608347 39328292
               39058237 38528203 38168236 38248405 38238478 38218574
               38388648 38528728 38718756 39128771 39298662