ZCZC SPCSWOMCD ALL
ACUS11 KWNS 190041 
SPC MCD 190041 
WIZ000-ILZ000-IAZ000-190215-

MESOSCALE DISCUSSION 1561
NWS STORM PREDICTION CENTER NORMAN OK
0741 PM CDT THU AUG 18 2016

AREAS AFFECTED...SRN WI...NERN IA...NWRN IL

CONCERNING...SEVERE THUNDERSTORM WATCH 450...451...

VALID 190041Z - 190215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
450...451...CONTINUES.

SUMMARY...AN ISOLATED DAMAGING WIND RISK CONTINUES WITH THE
CONVECTIVE SYSTEM MOVING INTO SOUTHERN WI/NORTHEAST IA. OTHER
ISOLATED STORMS ACROSS NORTHWEST IL WILL BE CAPABLE OF LOCALLY
SEVERE HAIL. ADDITIONAL WATCH ISSUANCE BEYOND THE CONFINES OF WW
450/451 IS NOT ANTICIPATED.

DISCUSSION...AT 0030Z...A BOWING THUNDERSTORM CLUSTER CONTINUES
MOVING ESEWD ACROSS NERN IA/SWRN WI. SOME WEAKENING HAS BEEN
NOTED...LIKELY DUE TO INCREASINGLY WEAK VERTICAL SHEAR /AS NOTED IN
00Z DVN SOUNDING/ AND THE ONSET OF DIURNAL BOUNDARY-LAYER
DESTABILIZATION. HOWEVER...A LOCAL DAMAGING WIND RISK WILL CONTINUE
FOR ANOTHER 1-2 HOURS IN AREAS ALONG THE LEADING EDGE OF THE COLD
POOL WHERE VIGOROUS CONVECTION REMAINS. 

AN ADDITIONAL STRONG ISOLATED STORM HAS DEVELOPED ACROSS NWRN IL.
WEAK VERTICAL SHEAR SHOULD LIMIT THE LONGEVITY OF THIS STORM...BUT A
LOCALIZED HAIL AND DOWNBURST RISK WILL EXIST WITH THIS STORM AND ANY
OTHER CELLS THAT DEVELOP AHEAD OF THE MAIN CONVECTIVE SYSTEM...GIVEN
STRONG BUOYANCY THAT IS IN PLACE. IN ADDITION...THE WEAKENING
CONVECTIVE SYSTEM TO THE NORTH WILL MOVE INTO PORTIONS OF ERN
IA/NWRN IL SOUTH OF WW 450/451 BETWEEN 01-02Z...WITH SOME POTENTIAL
FOR LOCALLY STRONG WIND GUSTS. HOWEVER...ADDITIONAL WATCH ISSUANCE
IS NOT CURRENTLY ANTICIPATED GIVEN THE INCREASINGLY MARGINAL NATURE
OF THE THREAT.

..DEAN/GRAMS.. 08/19/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GRB...LOT...MKX...DVN...ARX...DMX...

LAT...LON   43009276 43369162 43479113 44019125 44119067 44198982
            43888932 43028895 42498902 42168916 41918964 42019045
            42409213 42659268 43009276 

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