National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KPSR 161538
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
838 AM MST THU MAY 16 2013

.SYNOPSIS...
DRY WESTERLY FLOW ALOFT WILL LEAD TO GENERALLY SUNNY DAYS AND CLEAR
NIGHTS FOR THE REST OF THIS WEEK AND INTO THE WEEKEND. A DRY WEATHER
SYSTEM PASSING BY MAINLY TO OUR NORTH FRIDAY INTO SATURDAY WILL
BRING A FEW MID AND HIGH CLOUDS AND WILL ALSO LEAD TO A COOLING
TREND...WITH HIGH TEMPERATURES FALLING A BIT BELOW NORMAL BY
SATURDAY. HIGHS TEMPERATURES WILL THEN START TO WARM AGAIN SUNDAY
INTO EARLY NEXT WEEK.

&&

.DISCUSSION...
SAVE FOR SOME THIN HIGH CIRRUS WISPS...SKIES ARE CLEAR THIS MORNING
ACROSS THE FORECAST AREA. MORNING INVERSION LAYER ESTIMATED NEAR
925MB /NEAR 2500FT/ PER MORNING AIRCRAFT SOUNDINGS OUT OF KPHX. THIS
SHOULD QUICKLY MIX OUT BY THE LATE MORNING...WITH AFTERNOON
TEMPERATURES FORECAST IN THE UPPER 90S TO LOW 100S TODAY. AREA PWATS
BELOW A QUARTER OF AN INCH WITH DRY WESTERLY FLOW EXPANDING OVER THE
AREA. CONDITIONS WILL REMAIN WARM AND DRY TODAY AND INTO THE
WEEKEND...THE NORM FOR MID MAY ACROSS THE SOUTHWEST DESERTS. NO
UPDATES PLANNED FOR TODAY/S FORECAST PACKAGE...DISCUSSION BELOW
STILL APPLIES.

&&

.PREVIOUS DISCUSSION /ISSUED AT 150 AM MST/PST/...
RECENT 00Z FLG SOUNDING INDICATED PWAT DOWN TO JUST 0.17
INCHES...AND PRETTY MUCH ALL OF THE MID LEVEL MOISTURE THAT HAD LED
TO SOME CONVECTION OVER THE HIGHER TERRAIN OF EASTERN AZ THE PAST
FEW DAYS...HAS MOVED OFF INTO NEW MEXICO. DRY WESTERLY FLOW ALOFT
WILL LEAD TO SUNNY SKIES TODAY WITH LITTLE CHANGE IN HIGH
TEMPS...DESERT HIGHS WILL STILL REACH INTO THE TRIPLE DIGITS OVER
THE WARMER LOCALES.

GUIDANCE REMAINS CONSISTENT IN CALLING FOR A PROGRESSIVE AND OPEN
WAVE TROF TO MOVE ACROSS THE AREA FRIDAY INTO SATURDAY...AND THE
PROGS HAVE STOPPED THE DEEPENING TREND WITH THIS TROF. IT WILL BE A
DRY SYSTEM GIVING US BREEZY TO LOCALLY WINDY CONDITIONS FRIDAY...
ALONG WITH A COOLING TREND. THICKNESS VALUES LOWER 60-80M DURING THE
TWO DAY PERIOD AND DESERT HIGHS WILL FALL INTO THE LOW TO MID 90S BY
SATURDAY. THERE WILL BE SOME MID/HI CLOUDS PASSING THRU AHEAD OF THE
TROF FRIDAY LEADING TO PARTLY CLOUDY SKIES BUT SUNNY SKIES WILL
RETURN BY SATURDAY AFTERNOON.

DRY NORTHWEST FLOW ALOFT IN THE WAKE OF THE DEPARTING TROF WILL SET
UP ACROSS THE AREA SUNDAY INTO THE EARLY PORTION OF NEXT
WEEK...LEADING TO SUNNY DAYS...CLEAR NIGHTS...A GRADUAL WARMING
TREND...AND ONLY LOCAL AFTERNOON AND EVENING BREEZINESS. TRIPLE
DIGITS WILL RETURN TO THE WARMEST DESERTS BY NEXT MONDAY...AND
BECOME MORE WIDESPREAD BY TUESDAY. BOTH GFS AND ECMWF CALL FOR A
RATHER DEEP UPPER LOW TO DEVELOP ALONG THE PACIFIC NW COAST BY THE
MIDDLE OF NEXT WEEK...WHICH WILL GENERATE SOME INCREASE IN WIND BY
NEXT WEDNESDAY...MAINLY OVER OUR SERN CA ZONES.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA...INCLUDING KPHX...KIWA...KSDL...
MOSTLY CLEAR SKIES WILL PERSIST THROUGH FRIDAY MORNING...WITH WINDS
THE PRIMARY AVIATION CONCERN. WINDS SHOULD SHIFT TO W/SW BY LATE
MORNING...BECOMING GUSTY DURING THE MID AFTERNOON THROUGH EARLY
EVENING. THERE MAY BE A PERIOD OF PREDOMINANT SOUTH WINDS AT KPHX
LATE MORNING...HOWEVER SPEEDS SHOULD REMAIN BELOW 8KT LIMITING
PROBLEMS WITH CROSS WINDS BEFORE VEERING IN THE AFTERNOON. TIMING
TRENDS FOR GUSTS AND DRAINAGE REVERSAL WERE A COMBINATION OF
PERSISTENCE AND MODEL GUIDANCE.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA...INCLUDING KIPL AND KBLH...
MOSTLY CLEAR SKIES WILL PERSIST THROUGH FRIDAY MORNING WITH GUSTY
AFTERNOON AND EVENING WINDS THE MAIN AVIATION CONCERN. MODEL OUTPUT
SUGGESTS A PERSISTENCE TYPE FORECAST WITH RESPECT TO TIMING OF
DIRECTIONAL TRENDS AND GUSTINESS. SPEEDS MAY BE SOMEWHAT LOWER THAN
THOSE RECORDED WEDNESDAY...HOWEVER FREQUENT GUSTS ABOVE 20KT ARE
STILL EXPECTED AT TIMES THROUGH THE MID EVENING HOURS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
WIND SPEEDS WILL RELAX SOMEWHAT SATURDAY...WITH MORE TYPICAL SPEEDS
AND DIRECTIONS EXPECTED THROUGH THE PERIOD. SOUTH FACING SLOPES AND
RIDGE TOPS WILL STILL EXPERIENCE OCCASIONAL GUSTINESS...BUT FAR
WEAKER THAN THAT SEEN DURING THE MIDDLE OF THIS WEEK. TEMPERATURES
WILL COOL SLIGHTLY TO MORE SEASONABLE LEVELS OVER THE WEEKEND...WITH
A RENEWED WARMING TREND NEXT WEEK WHERE LOWER ELEVATIONS WILL SEE
HIGHS BREACHING 100F. 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.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...NOLTE
PREVIOUS DISCUSSION...CB
AVIATION...MO
FIRE WEATHER...CDEWEY/MO