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WWUS20 KWNS 090312

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IAZ000-ILZ000-MNZ000-WIZ000-091000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 594

NWS STORM PREDICTION CENTER NORMAN OK

1010 PM CDT SUN AUG 8 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND EASTERN IOWA

       NORTHWEST ILLINOIS

       SOUTHEAST MINNESOTA

       SOUTHWEST WISCONSIN



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 1010 PM UNTIL

500 AM CDT.



HAIL TO 1.5 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 95

STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES NORTH

NORTHWEST OF LA CROSSE WISCONSIN TO 15 MILES SOUTH SOUTHWEST OF

OTTUMWA IOWA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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 591...WW 592...WW 593...



DISCUSSION...DESPITE INCREASING CIN...IA MCS EXPECTED TO PERSIST

THROUGH EARLY MONDAY GIVEN STRENGTH OF CAPE...HI PW...AND LOW LVL

UPLIFT PROVIDED BY EXISTING COLD POOL.  AS COLD POOL CONTINUES TO

ELONGATE W-E BENEATH MODERATE WLY MID LVL FLOW...NERN PART OF MCS

SHOULD CONTINUE TO FORWARD-PROPAGATE TOWARD SW WI/NW IL...WITH

ASSOCIATED BOWING SEGMENTS CONTINUING TO YIELD ISOLD DMGG WIND

GUSTS.  ON TRAILING SWRN PART OF ELONGATING COLD POOL...SETUP SHOULD

SUPPORT CONTINUED DEVELOPMENT OF REGENERATIVE/TRAINING STORMS AS

SWLY LLJ STRENGTHENS.  THERMODYNAMIC ENVIRONMENT SUGGESTS THAT THESE

STORMS ALSO WILL HAVE THE POTENTIAL TO BOW...WITH THE BOWING

SEGMENTS TENDING TO TURN MORE SE TOWARD S CNTRL IA.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 29035.





...CORFIDI

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