Storm Prediction Center Mesoscale Discussion 134

   Mesoscale Discussion 0134
   NWS Storm Prediction Center Norman OK
   0530 PM CST Wed Mar 04 2026

   Areas affected...portions of the Ozarks into the lower Ohio River
   Valley

   Concerning...Severe Thunderstorm Watch 11...

   Valid 042330Z - 050130Z

   The severe weather threat for Severe Thunderstorm Watch 11
   continues.

   SUMMARY...The severe threat for all hazards continues across Severe
   Thunderstorm Watch #11 until 0300 UTC, with the primary threat for
   large hail and perhaps a tornado or two.

   DISCUSSION...MLCAPE of 1000-1500 J/kg coupled with effective bulk
   shear of 30-40 kts and modestly steep mid-level lapse rates of
   around 7 C/km will continue to favor a threat for severe hail across
   WW0011, primarily across portions of southern Missouri and northern
   Arkansas where an ongoing, isolated supercell may persist for at
   least another 1-2 hours. Increasing low-level flow is also expected
   to yield a modest increase to low-level hodograph curvature over the
   next few hours. With additional development across the southwestern
   portions of the Watch area possible, this will support at least some
   potential for an isolated tornado in addition to the continuing
   hail/wind threats, particularly where developing storms are able to
   maintain a more discrete storm mode.

   Farther northeast, a cluster of ongoing thunderstorms continues
   across portions of southern Illinois/Indiana along and north of the
   surface boundary. While instability and mid-level lapse rates are
   more limited (approximately 500 J/kg MUCAPE and 6 C/km,
   respectively, per latest mesoanalysis), modest warm air advection
   within the 925-850 mb layer atop the frontal boundary coupled with
   effective bulk shear around 30 knots will continue to support the
   risk for isolated severe hail over the next couple of hours. A
   downstream watch is not anticipated at this time.

   ..Chalmers/Lyons.. 03/04/2026

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

   ATTN...WFO...LMK...IND...PAH...ILX...MEG...LSX...LZK...SGF...

   LAT...LON   36149200 36409249 36859278 37379209 38668902 39068772
               39128726 39078658 38828613 38458614 38028653 37518728
               36898830 36009008 36149200 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN