Wednesday, April 17, 2013

Mesoscale Discussion 13:34:24.4837535

AREAS AFFECTED...S IOWA/N ILLINOIS/N MISSOURI

CONCERNING...SEVERE THUNDERSTORM WATCH 113...

VALID 171833Z - 171930Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 113
CONTINUES.

SUMMARY...THE SEVERE THREAT WILL LIKELY CONTINUE ACROSS WW113 OVER
THE NEXT FEW HOURS. THE MAIN SEVERE THREAT WILL BE HAIL...BUT A FEW
STRONG WIND GUSTS COULD ALSO OCCUR.

DISCUSSION...THUNDERSTORMS CONTINUE TO DEVELOP/PERSIST IN AN AREA OF
WAA ALONG AND NORTH OF A QUASI-STATIONARY BOUNDARY DRAPED ACROSS N
ILLINOIS...EXTENDING WWD INTO S IOWA. ALONG AND AHEAD OF THESE
THUNDERSTORMS THE ENVIRONMENT IS CHARACTERIZED BY MUCAPE VALUES
BETWEEN 500-1000 J/KG AND DEEP LAYER SHEAR AOA 50KTS. THIS WOULD
SUGGEST CONTINUED UPDRAFT ORGANIZATION..AND AN ATTENDANT SEVERE
WEATHER THREAT THROUGH THE AFTERNOON. HAIL APPEARS TO BE THE PRIMARY
THREAT...BUT ISOLATED DAMAGING WIND GUSTS CANNOT BE RULED OUT.

FARTHER WEST ACROSS WW113...ACROSS S IOWA...WAA WILL PERSIST
THROUGHOUT THE AFTERNOON. HERE...MUCAPE VALUES REMAIN AOA 500 J/KG
AND DEEP LAYER SHEAR SUFFICIENT FOR THUNDERSTORM ORGANIZATION.
ALTHOUGH THE INTENSITY OF THUNDERSTORMS APPEARS TO BE WANING...AN
ISOLATED SEVERE THREAT CANNOT BE RULED OUT.

..MARSH.. 04/17/2013

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

ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX...DMX...EAX...

LAT...LON 40569517 40579491 40909492 40899446 41159445 41179376
41529374 41509332 41889333 41869132 41959131 41939091
42289089 42299065 42519064 42488774 41678748 40998753
40988823 40618823 40618856 40748858 40738895 40588925
40338926 40318971 40418972 40448993 40219013 40189044
40269047 40279089 40179087 40199149 39929143 39939235
40029236 40039339 39949337 39959374 39789375 39739458
39839466 39839489 40259504 40279517 40569517