ACUS11 KWNS 141855
SWOMCD
SPC MCD 141855
INZ000-ILZ000-142100-

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