

679 

WWUS20 KWNS 080245

SEL2

SPC WW 080245

IAZ000-NEZ000-SDZ000-080800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 562

NWS STORM PREDICTION CENTER NORMAN OK

945 PM CDT TUE JUL 7 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWESTERN IOWA

       NORTHEASTERN NEBRASKA

       EXTREME SOUTHEASTERN SOUTH DAKOTA



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 945 PM

UNTIL 300 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 75

STATUTE MILES EAST AND WEST OF A LINE FROM 60 MILES WEST

NORTHWEST OF SPENCER IOWA TO 25 MILES WEST OF OMAHA NEBRASKA.

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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 560. WATCH NUMBER 560 WILL NOT

BE IN EFFECT AFTER 945 PM CDT. CONTINUE...WW 561...



DISCUSSION...ORGANIZED LINE OF THUNDERSTORMS AND ASSOCIATED COLD

POOL IS EXPECTED TO CONTINUE MOVING SWD THROUGH THE WW AREA THE NEXT

SEVERAL HOURS. DAMAGING WINDS WILL BE THE PRIMARY THREAT...THOUGH

SUFFICIENT DEEP LAYER SHEAR/INSTABILITY IS LOCATED AHEAD AND WEST OF

THE LINE...WHICH MAY RESULT IN ELEVATED STORMS WITH SEVERE HAIL.



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 500. MEAN STORM

MOTION VECTOR 34025.





...IMY

