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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 591

NWS STORM PREDICTION CENTER NORMAN OK

615 PM MDT SUN JUL 3 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN ARIZONA

       SOUTHEASTERN CALIFORNIA



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 615 PM UNTIL

100 AM MDT.



HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65

STATUTE MILES EITHER SIDE OF A LINE FROM 70 MILES NORTH NORTHWEST

OF THERMAL CALIFORNIA TO 90 MILES SOUTHEAST OF PHOENIX ARIZONA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).



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 588...WW 589...WW 590...



DISCUSSION...S CNTRL AZ MCS EXPECTED TO CONTINUE MOVING GENERALLY

WNW TO NW...GIVEN MODERATE ESELY 700-500 MB FLOW AND PRESENCE OF

RICHER MOISTURE/HIGH PW /AROUND 2 IN/ EXTENDING NWD THROUGH THE LWR

CO VLY.  LARGE TEMP-DEW POINT SPREADS...HIGH PW...AND AFOREMENTIONED

UNIDIRECTIONAL LWR TROPOSPHERIC FLOW SUGGEST POTENTIAL FOR BOWING

SEGMENTS/STORM MERGERS WITH HIGH WIND.  OTHER STORMS MAY FORM ON NRN

PERIPHERY OF ELONGATING COLD POOL...I.E. NEAR PHX AND POINTS E.

POSSIBLE STORM MERGERS IN THIS AREA ALSO COULD YIELD LOCALLY DMGG

WIND.



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

TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM

MOTION VECTOR 12025.





...CORFIDI

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