

000 

WWUS20 KWNS 102153

SEL9

SPC WW 102153

AZZ000-CAZ000-NVZ000-110500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 679

NWS STORM PREDICTION CENTER NORMAN OK

250 PM PDT THU JUL 10 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       A LARGE PART OF WESTERN ARIZONA

       PARTS OF SOUTHEASTERN CALIFORNIA

       SMALL PART OF SOUTHERN NEVADA



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

1000 PM PDT.



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 80

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTH

NORTHWEST OF KINGMAN ARIZONA TO 40 MILES EAST OF YUMA ARIZONA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 676...WW 677...WW 678...



DISCUSSION...SUBSTANTIAL INCREASE IN LOW LEVEL MOISTURE/INSTABILITY

HAS SPREAD NWD INTO EXTREME SRN NV FROM THE G OF C. THUNDERSTORMS

OVER HIGHER TERRAIN OF NWRN AZ WILL PROPAGATE W/SW INTO DESERT

VALLEYS WITH AN INCREASING THREAT OF DAMAGING WINDS.



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 07020.





...HALES

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