Storm Prediction Center Mesoscale Discussion 422

   Mesoscale Discussion 0422
   NWS Storm Prediction Center Norman OK
   0155 PM CDT Tue Apr 14 2026

   Areas affected...Parts of central IL into northern/central IN

   Concerning...Severe potential...Watch possible 

   Valid 141855Z - 142100Z

   Probability of Watch Issuance...40 percent

   SUMMARY...The area is being monitored for an increasing severe risk.
   While confidence in overall storm development/coverage and evolution
   remains uncertain, a watch issuance is possible this afternoon.

   DISCUSSION...In the vicinity of a remnant/increasingly diffuse
   outflow boundary draped across parts of northern/central IL, weak
   low-level warm advection is promoting gradually deepening cumulus
   and isolated convective initiation in central IL. Based on the
   motion of these echoes and character of the cumulus on day cloud
   phase imagery, this activity may be rooted above the boundary layer.
   Nevertheless, temperatures climbing into the lower 80s amid
   middle/upper 60s dewpoints will continue to erode inhibition at the
   base of the EML and could eventually support a transition to
   surface-based updrafts. If this were to occur, 2000-3000 J/kg MLCAPE
   and 40-50 kt of effective shear (characterized by a long/mostly
   straight hodograph) would initially favor discrete/semi-discrete
   supercells and clusters -- with a risk of very large hail (some 2+
   inches in diameter) and severe wind gusts. With time, a
   strengthening low-level jet will result in enlarging
   clockwise-curved hodographs (200-300 m2/s2 effective SRH) and an
   increasing supercell-tornado risk. 

   With all that said, the limited/nebulous synoptic and mesoscale
   ascent casts uncertainty on storm development/coverage and overall
   evolution -- especially given lingering inhibition. Convective and
   environmental trends are being monitored, and a watch issuance is
   possible this afternoon.

   ..Weinman/Gleason.. 04/14/2026

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

   ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN...

   LAT...LON   39088910 39288995 39649033 40049057 40599064 41049034
               41428980 41578728 41458650 41168587 40298545 39698564
               39418603 39088910 

   MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN