

000 

WWUS20 KWNS 060940

SEL2

SPC WW 060940

IAZ000-MOZ000-061300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 242

NWS STORM PREDICTION CENTER NORMAN OK

440 AM CDT SUN MAY 6 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTH CENTRAL IOWA

       NORTH CENTRAL MISSOURI



EFFECTIVE THIS SUNDAY MORNING FROM 440 AM UNTIL 800 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 50

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH

NORTHEAST OF DES MOINES IOWA TO 15 MILES EAST SOUTHEAST OF

CHILLICOTHE MISSOURI.  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 241...



DISCUSSION...BOW ECHO HAS ORGANIZED OVER SOUTHWEST IA AND NORTHWEST

MO DURING THE NEXT 1-2 HOURS.  THESE STORMS WILL TRACK EASTWARD

ALONG THE IA/MO BORDER THROUGH THE EARLY MORNING HOURS WITH A

CONTINUED RISK OF DAMAGING WINDS AND HAIL.  ACTIVITY IS EXPECTED TO

WEAKEN AS IT APPROACHES EASTERN EDGE OF WATCH...DUE TO WEAKER

VERTICAL SHEAR AND LESSENING INSTABILITY.



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 450. MEAN STORM

MOTION VECTOR 27030.





...HART

