ZCZC SPCSWOMCD ALL
ACUS11 KWNS 261721 
SPC MCD 261721 
OHZ000-MIZ000-INZ000-261915-

Mesoscale Discussion 1164
NWS Storm Prediction Center Norman OK
1221 PM CDT Thu Jul 26 2018

Areas affected...Portions of southeastern MI...northeastern IN...and
northern OH

Concerning...Severe potential...Watch possible 

Valid 261721Z - 261915Z

Probability of Watch Issuance...40 percent

SUMMARY...Scattered thunderstorms will continue to develop in the
next few hours and could pose a threat for some wind damage,
although the severity and coverage of the threat may not be large
enough to need a Severe Thunderstorm Watch.

DISCUSSION...Forcing for ascent with a mid-level speed max, a weak
vorticity center, and a cold front is currently maximized over
southeastern MI where thunderstorms continue to increase in
coverage.  The strength of the forcing decreases substantially with
southwestward extent along the front, but should be sufficient to
initiate additional thunderstorms into northeastern IN through early
afternoon. 

While weak mid-level lapse rates and modest low-level wind speeds
will limit the severity and coverage of the threat, steep low-level
lapse rates, a moist boundary layer, and DCAPEs of 900-1200 J/kg
will contribute to enough instability/downdrafts to support some
damage with 45-50 kt surface wind gusts, especially those that can
transfer momentum from the stronger mid-level wind speeds that will
overspread the area later in the afternoon.  A Severe Thunderstorm
Watch may be needed but uncertainty in the severity and coverage of
the threat is currently large enough to assign a 40% likelihood at
this time.

..Coniglio/Hart.. 07/26/2018

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

ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...

LAT...LON   41718148 41158172 40638210 40328253 40068302 40088413
            40158552 40428637 40958637 41278611 41708518 42298375
            42708296 42958240 42788191 42438158 41718148 

NNNN