

000 

WWUS20 KWNS 162258

SEL9

SPC WW 162258

AZZ000-170400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 609

NWS STORM PREDICTION CENTER NORMAN OK

455 PM MDT THU AUG 16 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN AND CENTRAL ARIZONA



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 455 PM UNTIL

1000 PM MDT.



HAIL TO 1 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 EAST AND WEST OF A LINE FROM 55 MILES NORTHWEST OF

PHOENIX ARIZONA TO 65 MILES EAST SOUTHEAST OF GILA BEND 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 605...WW 606...WW

607...WW 608...



DISCUSSION...TSTMS HAVE CONSOLIDATED ON PARTS OF AZS ERN RIM IN THE

PAST HOUR...WITH STRONG HEATING CONTINUING IN DEEPLY MIXED

ENVIRONMENT OVER THE LWR DESERTS TO THE WEST.  GIVEN MODEST BUT

FAIRLY DEEP LYR OF UNIDIRECTIONAL ELY FLOW...EXPECT ORGANIZED W/WSW

STORM PROPAGATION TO CONTINUE.  COUPLED WITH LARGE T/TD SPREADS IN

THE LWR DESERTS...SETUP COULD SUPPORT SCTD SWATHS OF DAMAGING

DOWNDRAFTS THROUGH MID EVENING.



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

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION

VECTOR 08015.





...CORFIDI

