525 FXUS65 KPSR 050435 AFDPSR AZZ020>028-CAZ030>033-051045- SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 935 PM MST WED DEC 4 2002 .SYNOPSIS... HIGH PRESSURE MOVING IN FROM THE WEST WILL BRING FAIR WEATHER AND WARMER DAYTIME TEMPERATURES TONIGHT THROUGH FRIDAY ACROSS SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. THEN...A LOW PRESSURE SYSTEM IS EXPECTED TO MOVE ACROSS NORTHERN ARIZONA SATURDAY...JUST BRUSHING SOUTH-CENTRAL ARIZONA WITH A SLIGHT CHANCE OF SHOWERS OVER HIGHER TERRAIN TO THE EAST OF PHOENIX. THIS SYSTEM WILL BE FOLLOWED BY A HIGH PRESSURE SYSTEM ON SUNDAY AND MONDAY...BRINGING FAIR WEATHER AND SLIGHT WARMING. ANOTHER FAST-MOVING LOW PRESSURE DISTURBANCE WILL MOVE ACROSS THE REGION TUESDAY AND TUESDAY NIGHT...WITH SOME COOLING REGION-WIDE AND POSSIBLE SHOWERS OVER THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA TO THE EAST OF PHOENIX. .DISCUSSION... NO SIGNIFICANT WEATHER PROBLEMS ON TAP FOR TONIGHT...THO THERE MAY STILL BE SOME VISIBILITY RESTRICTIONS OVER THE SCNTRL DESERTS PER MIST OR HAZE TONIGHT INTO TOMORROW AS THE AMS REMAINS RATHER HUMID AND PARTICULATE-FILLED. UPPER RIDGE IS NOW BUILDING OVER THE SWRN STATES WITH THE AXIS OVER NRN CA...AND THE RIDGE WILL SLOWLY MOVE EAST OVER THE NEXT 24-36 HOURS...KEEPING THE AIRMASS DRY AND STABLE. SHOULD SEE SOME INCREASE IN HIGH CLOUDS FROM THE WEST LATER TONIGHT AND THRU TOMORROW AHEAD OF A PACIFIC TROF THAT WILL MOVE INLAND FRIDAY. STILL...THE HIGH CLOUDS SHOULD BE SOMEWHAT ON THE THIN SIDE AND MOSTLY SUNNY SKIES SHOULD BE THE RULE MOST PLACES THU. WINDS TONIGHT WILL REMAIN LIGHT PER THE WEAK SFC/MID LEVEL GRADIENTS... AND THE SKIES WILL BE CLEAR. WED WAS VERY HAZY OVER THE PHX AREA...WITH VSBYS DOWN TO 3 MILES MOST OF THE DAY...AND INTO TONIGHT. WITH THE VERY STABLE AMS AND NO WIND TO STIR THINGS UP OR TO SCOUR OUT THE RH AND LOW LEVEL PARTICULATES...EXPECT THE HAZY/FOGGY CONDITIONS TO PERSIST TONIGHT AND CONTINUE TOMORROW AND THIS IS ALREADY IN THE FORECAST. NO CHANGES NEEDED TO CURRENT PACKAGE. 11 .PSR...NONE.