ZCZC SPCSWOMCD ALL
ACUS11 KWNS 201629 
SPC MCD 201629 
MIZ000-OHZ000-INZ000-201730-

Mesoscale Discussion 1521
NWS Storm Prediction Center Norman OK
1129 AM CDT Wed Jul 20 2022

Areas affected...portions of Lower Michigan into northeastern
Indiana and northwestern Ohio

Concerning...Severe potential...Watch likely 

Valid 201629Z - 201730Z

Probability of Watch Issuance...80 percent

SUMMARY...Thunderstorm development is expected to begin over the
next hour, accompanied by an increase in severe risk.  WW issuance
may be required.

DISCUSSION...Latest visible satellite and radar loops show
convection developing across parts of central and eastern Lower
Michigan at this time, near and ahead of an advancing surface cold
front.  The moist boundary layer ahead of the front -- characterized
by dewpoints around 70 -- has continued to heat through midday,
which has now pushed mixed-layer CAPE values into the 1500 to 2500
J/kg range.  Continued/gradual heating will support continued
destabilization, and a corresponding increase in convective
development/eventual storm initiation.

Moderately strong cyclonic/southwesterly flow currently resides
across Lower Michigan, on the southeastern side of the upper low
moving eastward across central portions of the U.P.  Resulting shear
-- around 35 kt per a combination of VWP data and RAP soundings --
suggests potential for organized storms, including a couple of
supercells initially, later possibly growing upscale locally into
small-scale bands.  While a tornado can't be ruled out, primary
severe risk will likely manifest as locally damaging gusts.  Current
indications are that storm coverage -- and thus degree of severe
risk -- will likely increase sufficient to warrant WW consideration
over the next half hour or so.

..Goss/Hart.. 07/20/2022

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

ATTN...WFO...CLE...DTX...APX...IWX...GRR...

LAT...LON   43988453 44068291 43208243 41288300 41048403 41298526
            41878543 42628505 43988453 

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