

077 

WWUS20 KWNS 052315

SEL1

SPC WW 052315

IAZ000-060400-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 601

NWS STORM PREDICTION CENTER NORMAN OK

610 PM CDT TUE JUL 5 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHERN IOWA



EFFECTIVE THIS TUESDAY EVENING FROM 610 PM UNTIL 1100 PM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH NORTHWEST OF

DES MOINES IOWA TO 15 MILES EAST OF LAMONI IOWA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU1).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 600...



DISCUSSION...ISOLD SUPERCELL HAS FORMED IN CNTRL IA...ALONG

INFLECTION IN BOUNDARY ARCING ESE FROM NEAR SLB TO S OF FOD TO E OF

DSM.  OTHER STORMS MAY FORM A BIT LATER THIS EVE ALONG THAT PART OF

BOUNDARY W OF CURRENT STORM.  LOW LVL WIND FIELD IS WEAK.  BUT

ORIENTATION OF BOUNDARY AND LOW LVL INSTABILITY AXIS...IN

CONJUNCTION WITH 40+ KT NWLY 500 MB FLOW...IS RESULTING IN

SIGNIFICANT DEVIATE STORM MOTION.  COUPLED WITH MOIST LOW LVL

ENVIRONMENT...THIS MAY CONTINUE TO SUPPORT EPISODES OF ENHANCED LOW

LVL ROTATION AND POSSIBLY A COUPLE TORNADOES GIVEN SUPERCELLULAR

NATURE OF STORM/S/.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 34025.





...CORFIDI

