Storm Prediction Center Mesoscale Discussion 217

   Mesoscale Discussion 0217
   NWS Storm Prediction Center Norman OK
   1250 PM CDT Wed Mar 11 2026

   Areas affected...portions of the upper Ohio River Valley into the
   northern Mid-Atlantic

   Concerning...Tornado Watch 42...45...

   Valid 111750Z - 111915Z

   The severe weather threat for Tornado Watch 42, 45 continues.

   SUMMARY...Thunderstorms will gradually spread eastward through this
   afternoon within an environment supportive of a mix of line segments
   and supercells. Damaging wind gusts, a couple of tornadoes, and
   perhaps isolated large hail are possible.

   DISCUSSION...Several low-topped supercells have exhibited some
   strengthening across portions of eastern Ohio over the past 30
   minutes. This activity, along with additional development, is
   expected to persist eastward into this afternoon. Filtered diurnal
   heating of a moist low-level air mass (dewpoints in the upper 50s to
   low 60s F) is expected to support 1000-1500 J/kg MLCAPE this
   afternoon amidst strong deep-layer shear of 50+ kts. As increasing
   upper-level ascent overspreads the region, convective coverage is
   forecast to increase, with a mix of supercells and line segments
   expected through the afternoon. While poor mid-level lapse rates are
   expected to limit the overall threat, strong low-level flow (60+ kts
   at 1 km AGL per the PBZ VWP) will yield enough low-level shear to
   support some risk for damaging wind gusts and a couple of tornadoes.
   Any supercells that are able to remain discrete may also pose a risk
   for isolated large hail given the aforementioned strong deep-layer
   shear.

   ..Chalmers/Gleason.. 03/11/2026

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

   ATTN...WFO...CTP...LWX...PBZ...RLX...ILN...

   LAT...LON   38398150 38448198 38518230 38658245 38868251 39128257
               39448254 39698250 39848238 40008197 40318111 40468065
               40578012 40587961 40607902 40507846 40267798 40097784
               39897783 39587782 39277795 38977822 38707871 38507924
               38427983 38388066 38398150 

   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