MESOSCALE DISCUSSION 1790
   NWS STORM PREDICTION CENTER NORMAN OK
   0803 PM CDT TUE JUL 27 2004
   
   AREAS AFFECTED...PARTS OF CENTRAL/SERN AZ
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 670...
   
   VALID 280103Z - 280230Z
   
   POTENTIALLY SEVERE TSTMS OVER GILA COUNTIES ATTM...AND STRONG
   CONVECTION SEWD ACROSS GRAHAM COUNTY...MAY PRODUCE DAMAGING GUSTS IN
   NEXT HOUR BEFORE WEAKENING.  ANOTHER AREA OF TSTMS HAS MOVED INTO
   NRN MARICOPA COUNTY AND PRODUCED AN OUTFLOW POOL THAT IS SURGING
   AWAY FROM HIGHEST REFLECTIVITIES ATTM. OUTFLOW BOUNDARY SHOULD
   CONTINUE TO SURGE SWD ACROSS REMAINDER PHX AREA AND OVER PORTIONS
   SRN MARICOPA/WRN PINAL COUNTIES BEFORE DISSIPATING. 
   MEANWHILE...PARENT CONVECTION NOW OVER NRN PHX METRO WILL MOVE SEWD
   AND WEAKEN...PRODUCING OCCASIONAL GUSTS NEAR SEVERE LEVELS.  WIND
   DAMAGE POTENTIAL OVERALL SHOULD DECREASE MARKEDLY AFTER ABOUT
   ANOTHER HOUR OVER THIS REGION...BECAUSE OF EXPANDING OUTFLOW
   POOLS...WEAKENING DIABATIC HEATING AND DIMINISHING CONVECTIVE
   TRENDS.  REMAINDER WW PROBABLY WILL BE ALLOWED TO EXPIRE AS
   SCHEDULED AT 02Z WITHOUT FURTHER ISSUANCE.
   
   ..EDWARDS.. 07/28/2004
   
   
   ATTN...WFO...EPZ...TWC...FGZ...PSR...
   
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