ZCZC SPCSWOMCD ALL
ACUS11 KWNS 022355 
SPC MCD 022355 
INZ000-ILZ000-030200-

Mesoscale Discussion 0629
NWS Storm Prediction Center Norman OK
0655 PM CDT Sat Jun 02 2018

Areas affected...Portions of central/eastern IL and far western IN

Concerning...Severe potential...Watch unlikely 

Valid 022355Z - 030200Z

Probability of Watch Issuance...5 percent

SUMMARY...A very isolated large hail and strong to locally damaging
wind threat may exist for the next couple of hours. Watch issuance
is not expected.

DISCUSSION...It appears that weak low-level convergence along a
remnant outflow boundary and modest low-level warm air advection is
responsible for a recent uptick in convection across parts of
central/eastern IL. A warm and moist low-level airmass across this
region is contributing to MLCAPE around 1000-2000 J/kg per 23Z RAP
mesoanalysis. Stronger mid-level westerly flow associated with an
upper trough over the Upper Midwest and upper MS Valley remains
generally displaced to the west of ongoing thunderstorm activity.
Still, enough veering and modest strengthening of the low/mid-level
flow exists in RAP forecast soundings to support around 30-35 kt of
effective bulk shear. Several recent updrafts across eastern IL have
shown robust vertical development, and very isolated large hail and
strong to locally damaging winds will be possible for the next
couple of hours. The loss of daytime heating later this evening will
reduce instability and lessen the already marginal severe threat.
Therefore, watch issuance is not expected.

..Gleason/Grams.. 06/02/2018

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

ATTN...WFO...IND...LOT...ILX...

LAT...LON   39528895 40518908 41008908 41278895 41428842 41228773
            41048723 39138717 38888764 38918860 39528895 

NNNN