ZCZC SPCSWOMCD ALL
ACUS11 KWNS 131219 
SPC MCD 131219 
INZ000-MIZ000-ILZ000-131345-

MESOSCALE DISCUSSION 1389
NWS STORM PREDICTION CENTER NORMAN OK
0719 AM CDT MON JUL 13 2015

AREAS AFFECTED...NRN IL THROUGH NWRN IND

CONCERNING...SEVERE THUNDERSTORM WATCH 408...

VALID 131219Z - 131345Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 408
CONTINUES.

SUMMARY...SQUALL LINE WILL CONTINUE TO POSE A THREAT FOR ISOLATED
STRONG TO DAMAGING WIND NEXT 2-3 HOURS AS IT MOVES SSEWD THROUGH NRN
IL INTO NWRN IND. THESE STORMS WILL BEGIN TO MOVE SOUTH OF WW 408
AFTER 1230Z...AND ADDITIONAL COUNTIES CAN BE LOCALLY ADDED AS
NECESSARY THROUGH THE REMAINDER OF CHICAGO CWA. ANOTHER WW WILL NEED
TO BE CONSIDERED FOR PARTS OF ECNTRL IL THROUGH NRN IND A BIT LATER
THIS MORNING.

DISCUSSION...SQUALL LINE EXTENDING FROM NRN IL THROUGH SRN LAKE MI
IS MOVING SEWD AT 30-40 KT. THE STORMS SHOULD PERSIST NEXT FEW HOURS
THROUGH SWRN LOWER MI...NWRN IND AND ECNTRL IL ALONG INSTABILITY
GRADIENT PROMOTED BY CONVERGENCE INDUCED BY A 30 KT WSWLY LLJ
INTERACTING WITH THE CONVECTIVE OUTFLOW BOUNDARY. THE VWP FROM
MILWAUKEE WI ALSO INDICATES 40-50 KT NWLY LOW-MID LEVEL WINDS IN
POST SQUALL LINE REGIME THAT APPEARS TO BE IN PART CONVECTIVELY
INDUCED. VISIBLE IMAGERY SHOWS MOSTLY CLEAR SKIES OVER CNTRL
IL...BUT WITH ANVIL DEBRIS SPREADING INTO NRN IND. WHILE THE LINE
HAS SHOWN AT LEAST A SLIGHT WEAKENING TREND...SOME REINTENSIFICATION
IS PROBABLE LATER THIS MORNING AS THE BOUNDARY LAYER BEINGS TO WARM.

..DIAL.. 07/13/2015

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

ATTN...WFO...IWX...LOT...ILX...

LAT...LON   41568912 41748808 41948720 41718622 41298609 40638690
            40468822 41028909 41568912 

NNNN