999 
FXUS65 KPSR 172151
AFDPSR

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
245 PM MST WED MAR 17 1999

.SYNOPSIS...
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE SLOWLY EAST
ACROSS THE STATE TONIGHT...WITH CLOUDINESS TO GRADUALLY DECREASE FROM
THE WEST...LEAVING MOSTLY CLEAR TO PARTLY CLOUDY SKIES BY MORNING.
HIGHER PRESSURE ALOFT WILL BRING MOSTLY SUNNY SKIES TO MOST AREAS
THURSDAY...WITH SUNNY CONDITIONS TO CONTINUE FRIDAY. HIGH CLOUDS
SHOULD INCREASE OVER SOUTHEAST CALIFORNIA AND WESTERN ARIZONA
SATURDAY AHEAD OF THE NEXT PACIFIC SYSTEM...AND THIS SYSTEM COULD
BRING SHOWERS BY SUNDAY...CONTINUING INTO MONDAY. 

.DISCUSSION...
CLOSED UPPER LOW CONTINUES TO TREK SLOWLY EWD ACRS AZ...WITH THE LOW
CENTER OVER FAR SERN AZ AT 2 PM. SIGNIFICANT WRAP AROUND MSTR OVER
MOST OF THE STATE...WITH THE BACK EDGE OF CLDS NR THE WRN MARICOPA
CTY BORDER. 88D INDICATES THAT SHOWERS HAVE GREATLY DECREASED...AND
SHOULD JUST BE A FEW LINGERING LIGHT ONES DURG THE EVE HOURS OVER FAR
ERN PTNS OF THE PHX CWA. SAT PIX SHOW SOME BREAKUP AND THINNING OF
THE THICK CLOUD BANDS ROTG ARND THE BACK SIDE OF THE LOW. WILL GO
WITH AN AVN/NGM MIX FOR THE FORECAST...AS THEY INITIALIZED LOW OK AND
ETA APPEARS A TAD TOO FAST. SHOULD SEE A GRADUAL DECREASE IN CLOUDS
ACROSS THE CWA..FM THE W...TONIGHT...WITH SKIES MOSTLY CLEAR W TO
PARTLY CLOUDY E BY MORNING. HIGH PRESSURE TO SET UP OVER THE STATE ON
THU...FOR GENLY SUNNY SKIES AND RATHER LIGHT WINDS...ALONG WITH
WARMER TEMPS. COULD SEE ENOUGH LINGERING LOW LVL MSTR AROUND THE FAR
ERN PARTS OF THE CWA FOR SOME PARTLY CLOUDY SKIES ON THU. CONTD SUNNY
SKIES ON FRI AS THE RIDGE DOMINATES THE WEATHER PATN. NEXT SHOT FOR
WX IN THE EXTENDED PERIOD...LOOKS TO BE A SUNDAY STORM...AND MOST OF
THE MOISTURE AND DYNAMICS SHOULD BE CONFINED TO THE NRN HALF OF THE
STATE. WILL CONTINUE THE FORECAST OF A CHANCE FOR SHOWERS ON
SUN...AND SINCE THE PROGS HAVE TYPICALLY BEEN A BIT TOO FAST...WILL
LINGER THE SHOWERS IN THE CWA ON MON MORNING...AND DROP THE WORDING
OF THE SHOWERS ON SAT. WX FOR SAT SHOULD BE OK...WITH INCREASING
CLOUDS AND WIND AHEAD OF THE SUNDAY EVENT. MAIN COOLING WILL BE ON
SUNDAY...WITH A BIT OF A REBOUND ON MON. 11