ZCZC SPCSWOMCD ALL
ACUS11 KWNS 190153 
SPC MCD 190153 
INZ000-ILZ000-190330-

Mesoscale Discussion 1002
NWS Storm Prediction Center Norman OK
0853 PM CDT Fri Jun 18 2021

Areas affected...portions of central/southern IL

Concerning...Severe potential...Watch likely 

Valid 190153Z - 190330Z

Probability of Watch Issuance...80 percent

SUMMARY...A small cluster of severe thunderstorms will move
east/southeast this evening with large hail and damaging winds the
main threats.  Additional thunderstorm development is anticipated,
and a watch will likely be needed prior to 03z.

DISCUSSION...A small cluster of thunderstorms has developed near
Springfield, IL as of 0150z, in the vicinity of an east-west front. 
Strong surface-based instability remains in place along with 30-35
kts of effective shear, favoring supercells initially with a risk
for large hail, potentially significant, in addition to damaging
downburst winds.  Strengthening warm advection this evening will
contribute to additional thunderstorm development, with storms
evolving into bowing segments with time and continuing to pose a
severe risk into the early overnight hours.  

Observational trends are being monitored and a watch is likely prior
to 03z.

..Bunting/Guyer.. 06/19/2021

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

ATTN...WFO...IND...PAH...ILX...LSX...DVN...

LAT...LON   38518794 38678951 39029036 39739113 40249124 40439103
            40469035 40258921 39998816 39868766 38958757 38518794 

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