Storm Prediction Center Mesoscale Discussion 2284

   Mesoscale Discussion 2284
   NWS Storm Prediction Center Norman OK
   0658 PM CST Sun Dec 28 2025

   Areas affected...central Indiana...western Kentucky and
   Tennessee...extreme southern Illinois

   Concerning...Tornado Watch 643...

   Valid 290058Z - 290400Z

   The severe weather threat for Tornado Watch 643 continues.

   SUMMARY...Areas of damaging gusts or perhaps a brief tornado remain
   possible from central Indiana southwestward into the lower Ohio
   Valley. Sporadic damaging gusts cannot be ruled out as far south as
   western Tennessee.

   DISCUSSION...A line of thunderstorms continues to move rapidly east
   coincident with the cold front, with indications of QLCS storm mode
   at times. Convective trends may be dwindling across the far northern
   areas, as the line encounters a relatively cooler boundary layer.
   Farther south toward the OH River and toward western KY and TN,
   temperatures remain in the 70s F with lower 60s F dewpoints. This is
   generally resulting in MLCAPE values of a few hundred J/kg. However,
   little instability is needed to persist the damaging wind threat as
   the line is strongly forced and with 50 kt around 1 km AGL.
   Low-level SRH is also strong with 0-1 km values to 400 m2/s2.

   Given the loss of heating and rapidly moving cold front, the severe
   storms risk is expected to last a few hours until the line pushes
   through the narrow instability axis. In the near term, the greatest
   risk areas continues to be within the tornado watch extending from
   central IN into western KY, and the watch may be locally extended in
   time or space as conditions warrant.

   ..Jewell.. 12/29/2025

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

   ATTN...WFO...ILN...LMK...OHX...IND...PAH...MEG...

   LAT...LON   36048994 37408883 38448738 39798622 40208580 40198535
               39688521 38788545 37978603 36698737 35938842 35718910
               35708968 35888995 36048994 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN