

228 

WWUS20 KWNS 082215

SEL2

SPC WW 082215

IAZ000-090500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 442

NWS STORM PREDICTION CENTER NORMAN OK

520 PM CDT WED JUN 8 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL IOWA



EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 520 PM UNTIL MIDNIGHT CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 50

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTHEAST

OF WATERLOO IOWA TO 55 MILES WEST NORTHWEST OF LAMONI IOWA.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 440...WW 441...



DISCUSSION...THUNDERSTORMS ARE RAPIDLY FORMING ALONG A FRONT OVER

CENTRAL IA.  ACTIVITY WILL BE MOVING INTO A VERY MOIST AND UNSTABLE

AIR MASS...WITH SUFFICIENT VERTICAL SHEAR FOR ORGANIZED SEVERE

STORMS.  LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE

STRONGER CELLS THROUGH THE EVENING.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 26025.





...HART

