143
ACUS11 KWNS 121642
SWOMCD
SPC MCD 121642
OHZ000-KYZ000-INZ000-ILZ000-MOZ000-121915-

Mesoscale Discussion 1655
NWS Storm Prediction Center Norman OK
1142 AM CDT Sat Jul 12 2025

Areas affected...IN...western/central OH...northern/western
KY...southern IL...southeast MO

Concerning...Severe potential...Watch possible

Valid 121642Z - 121915Z

Probability of Watch Issuance...40 percent

SUMMARY...Storms capable of isolated to scattered damaging winds are
possible this afternoon.

DISCUSSION...A diffuse cold front is currently moving across parts
of IL/IN, with evidence of a gravity wave preceding the front from
northwest OH into east/central IN. Cumulus is gradually building in
the vicinity of this prefrontal feature, with recent storm
initiation noted across far northwest OH. With weak midlevel lapse
rates in place, initial convection may only gradually intensify.
However, rich moisture and MLCAPE increasing into the 1500-2500 J/kg
range could eventually support more robust storm development
along/ahead of the cold front this afternoon. Deep-layer shear is
generally weak, but steepening low-level lapse rates and 20-30 kt of
southwesterly flow in the 850-700 mb layer may allow for a few
stronger outflow-driven clusters capable of isolated to scattered
damaging wind.

Farther southwest, a weak storm cluster is ongoing from southeast MO
into southern IL. Heating/destabilization ahead of this cluster may
allow for some intensification with time, accompanied by a threat
for at least isolated damaging winds as it moves generally
east-northeastward. Additional strong storms may develop in the wake
of this cluster later this afternoon, along the diffuse cold front
and any remnant outflow boundaries.

Coverage of the organized severe threat across the region remains
uncertain, but watch issuance is possible if a corridor of somewhat
greater damaging-wind potential becomes apparent.

..Dean/Mosier.. 07/12/2025

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

ATTN...WFO...CLE...ILN...LMK...IWX...IND...PAH...ILX...LSX...

LAT...LON   38048998 39468779 40478619 41658502 41718318 41348203
            39998306 38628486 37958616 37208804 36768958 37028995
            38048998

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