000
FXUS65 KPSR 152101
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
200 PM MST WED MAY 15 2013

.SYNOPSIS...
A WEAK WEATHER SYSTEM PASSING MAINLY TO THE NORTH TODAY WILL LEAD TO
SOME SLIGHTLY COOLER HIGH TEMPERATURES AND AN END TO PRECIPITATION
CHANCES OVER SOUTH-CENTRAL ARIZONA. CONDITIONS WILL REMAIN DRY
THROUGH THE WEEKEND. ANTICIPATE SOME MODEST COOLING FRIDAY AND
SATURDAY BEFORE TEMPERATURES START TO WARM AGAIN EARLY NEXT WEEK.

&&

.DISCUSSION...
REST OF TODAY THROUGH SATURDAY...CONSIDERABLY LESS CU/TOWERING CU
DEVELOPMENT EARLY THIS AFTERNOON THAN 24 HOURS AGO PER VISIBLE
SATELLITE IMAGERY. GPS-IPW STATIONS SHOW A CONTINUED DECLINE OF
PRECIPITABLE WATER...SOME STATIONS MORE THAN OTHERS. WELL DEFINED
SHORT WAVE/SOUTHERN BRANCH UPPER LOW NOW CENTERED OVER UTAH. AS THE
SYSTEM CONTINUES TO MOVE EAST ZONAL FLOW ALOFT WILL DEVELOP TONIGHT
FOLLOWED BY SOUTHWESTERLY FLOW THURSDAY AHEAD OF AN APPROACHING
TROUGH. MODELS IN GOOD AGREEMENT ON THE TROUGH MOVING ACROSS
CALIFORNIA AND THE INTERIOR WEST FRIDAY AND SATURDAY. SOME MINOR
DIFFERENCES ON THE DEPTH OF THE TROUGH AND THE TIMING. IT WILL BRING
COOLER TEMPERATURES BUT NO PRECIP CHANCES FOR OUR AREA. AFTERNOON
AND EVENING BREEZES WILL CONTINUE THOUGH WINDY CONDITIONS CAN BE
EXPECTED IN SOUTHEAST CALIFORNIA FRIDAY EVENING...ESPECIALLY
IMPERIAL COUNTY.

SUNDAY THROUGH WEDNESDAY...A DRIER NORTHWEST FLOW ALOFT WILL
SETTLE INTO THE DESERT SOUTHWEST IN THE WAKE OF THE DEPARTING OPEN
WAVE TROF. THIS WILL GIVE US SUNNY DAYS AND CLEAR NIGHTS ALONG WITH
A GRADUAL WARMING TREND. HIGHS SHOULD REACH BACK INTO THE TRIPLE
DIGITS OVER MOST OF THE WARMER DESERTS BY MONDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA...KSDL...
MOSTLY CLEAR SKIES WILL PERSIST THROUGH THURSDAY AFTERNOON...WITH
SOME BREEZY WEST WINDS IN THE AFTERNOON HOURS. LOW PRESSURE SITUATED
TO THE NORTHWEST WILL APPROACH THURSDAY INTO FRIDAY...BRINGING
BREEZY TO GUSTY WINDS ACROSS CENTRAL AND NORTHERN AZ AOB 25KTS.
WINDS SHIFTING TO DRAINAGE DOWNSLOPE DURING THE OVERNIGHT HOURS. SFC
PRESSURE GRADIENT RELAXES BY THURSDAY MORNING.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA...INCLUDING KIPL AND KBLH...
CLEAR SKIES WILL PERSIST THROUGH THURSDAY AFTERNOON WITH GUSTY WINDS
IN THE AFTERNOON AND EVENING. LIGHTER SFC WINDS CAN BE EXPECTED
BEYOND MID EVENING AND THROUGH THURS MORNING AS THE SFC PRESSURE
GRADIENT RELAXES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
ELEVATED WINDS FRIDAY WILL BEGIN TO RELAX SATURDAY AS AN ELONGATED
TROUGH MOVES ACROSS ARIZONA SATURDAY. MORE TYPICAL WIND SPEEDS AND
DIRECTIONS EXPECTED THROUGH THE PERIOD. TEMPERATURES WILL COOL
SLIGHTLY TO MORE SEASONABLE LEVELS OVER THE WEEKEND...WITH A RENEWED
WARMING TREND NEXT WEEK. NO PRECIPITATION IS EXPECTED THROUGH THE
ENTIRE PERIOD. MINIMUM HUMIDITY LEVELS WILL FALL BELOW 15
PERCENT...WITH MOST LOCATIONS DROPPING INTO THE SINGLE DIGITS EACH
DAY...WHILE OVERNIGHT RECOVERY WILL GENERALLY BE FAIR TO LOCALLY
POOR

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

$$

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DISCUSSION...AJ/CB
AVIATION...CDEWEY
FIRE WEATHER...CDEWEY