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000
FXUS65 KPSR 261713
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1010 AM MST SAT JUL 26 2014

.SYNOPSIS...
MONSOON MOISTURE WILL REMAIN ACROSS THE REGION THROUGH AT LEAST THE
MIDDLE OF NEXT WEEK...WITH A CHANCE FOR AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS EACH DAY. DAYTIME TEMPERATURES WILL STILL
HOLD ABOVE SEASONAL NORMALS...BUT ARE EXPECTED TO REMAIN BELOW THE
NEAR-RECORD READINGS WE SAW EARLIER THIS WEEK.

&&

.DISCUSSION...
IR/VIS SATELLITE IMAGERY THIS MORNING SHOWS MOSTLY SUNNY SKIES
ACROSS MOST OF THE REGION...WITH SOME MID-UPPER LEVEL CLOUDINESS
STREAKING OVER SOUTHEAST CALIFORNIA AND NORTHWEST ARIZONA INTO UTAH
THIS MORNING. SOME LIGHTNING IS ALSO NOTED WITH THE CLOUDS OVER
EXTREME NORTHWEST AZ...THIS ACTIVITY ASSOCIATED WITH A WEAK UPPER
LEVEL DISTURBANCE THAT WILL HELP KEEP ISOLATED STORMS FORMING ACROSS
PORTIONS OF NORTHWEST ARIZONA THROUGHOUT THE DAY. SURFACE TEMPS ARE
RUNNING ON AVERAGE ABOUT 3-5 DEGREES COOLER ACROSS OUR ARIZONA
FORECAST ZONES COMPARED TO THIS TIME YESTERDAY MORNING...THIS IN
PART DUE TO THE STORM ACTIVITY/PRECIPITATION THAT OCCURRED
OVERNIGHT. EVEN DEW POINT TEMPERATURES HAVE NOT CHANGED MUCH...
GENERALLY IN THE 60S CWA-WIDE...WITH PRECIPITABLE WATER STILL AROUND
1.25-1.50 INCHES PER THE KTWC/KPSR MORNING SOUNDINGS.

THE COOLER...MORE MOIST BOUNDARY LAYER CONDITIONS HAVE CREATED A
MORE STABLE ATMOSPHERE IN THE LOWER LEVELS. EVEN SO...WITH THE LACK
OF CLOUD COVER...AND GOOD DAY DAYTIME HEATING/INSOLATION...THE
POTENTIAL IS THERE TO OVERCOME THIS INHIBITION AND ONCE AGAIN GIN UP
THUNDERSTORMS...THIS TIME MAINLY OVER THE HIGHER TERRAIN/MOUNTAINS
NORTH AND EAST OF PHOENIX. EXPECT STORM ACTIVITY TO BE LESS OVER THE
SOUTH-CENTRAL DESERTS...INCLUDING MOST OF MARICOPA/PINAL COUNTIES...
AS THIS IS WHERE MOST OF THE STORMS AND BLOWING DUST OCCURRED
FRIDAY. OVERALL...THE UPPER LEVEL FLOW IS LESS FAVORABLE FOR
WIDESPREAD THUNDERSTORM DEVELOPMENT...SO STORMS WILL BE MORE
ISOLATED IN NATURE IF THEY FORM OVER THE LOWER DESERTS. EXPECT
DAYTIME TEMPS TO BE SIMILAR TO YESTERDAY...IN THE 105-110 RANGE
ACROSS THE LOWER DESERTS. OTHER THAN SOME ADJUSTMENTS TO REDUCE
CLOUD COVER IN THE GRIDS...SHORT TERM FORECAST APPEARS TO BE ON
TRACK. NO OTHER CHANGES AT THIS TIME.

PREVIOUS DISCUSSION...
SUNDAY THROUGH FRIDAY...IT APPEARS THAT A LOW-MID GRADE MONSOON WILL
LIKELY PREVAIL THROUGH AT LEAST TUESDAY. ALTHOUGH SOUTHERLY FLOW
ALOFT WILL CONTINUE TO PULL MOISTURE INTO THE REGION THROUGH THIS
PERIOD...LIGHT WINDS ALOFT AND THE TENDENCY FOR THE MAIN UPPER HIGH
CENTER TO REMAIN OVER/JUST EAST OF OUR REGION WILL LIKELY HAMPER TS
DEVELOPMENT EACH DAY...WITH INTERSECTING OUTFLOWS BEING THE PRIMARY
SOURCE OF LIFT FOR CONVECTIVE ACTIVITY. TS ACTIVITY COULD BE LESS
FROM TUESDAY ONWARD INTO THE END OF NEXT...SINCE THE GFS HINTS THAT
THE FLOW ALOFT COULD BECOME A MORE WESTERLY...AND DRIER ONE...BUT
CONFIDENCE IN THIS SOLN IS QUITE LOW...AND HAVE KEPT CLIMO-LIKE
VALUES IN THE POP GRIDS FOR NOW...WITH TEMPS IN THE NORMAL TO
SLIGHTLY-ABOVE NORMAL RANGE.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SCT TO BKN
MID AND HIGH LEVEL DEBRIS CLOUDS WILL GRADUALLY THIN THROUGH THE
DAY. VERY WARM TEMPERATURES AND AN ABUNDANCE OF MOISTURE WILL KEEP A
THREAT OF AFTN AND EVE THUNDERSTORMS OVER THE REGION. WITH LOW
CONFIDENCE ON THE LOCATION AND TIMING OF STORMS THOUGH...WE WILL
KEEP MENTION OF THUNDERSTORMS OUT OF TAFS RIGHT NOW. THEY WILL BE
ADDED LATER ON IF IT APPEARS TERMINALS WILL BE IMPACTED. WINDS WILL
BE GENERALLY LIGHT AND PREVAIL OUT OF THE SOUTHWEST...THOUGH COULD
BECOME VARIABLE AND GUSTY IF OUTFLOW BOUNDARIES PUSH ACROSS THE AREA.

SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT TO BKN MID AND HIGH LEVEL DEBRIS CLOUDINESS WILL WORK ITS WAY
INTO THE REGION THROUGH THE DAY. THE THREAT OF THUNDERSTORMS THIS
AFTERNOON AND EVENING WILL PRIMARILY REMAIN EAST OF THE COLORADO
RIVER VALLEY...THOUGH ISOLATED STORMS COULD WORK THEIR WAY INTO
SOUTHEAST CALIFORNIA. SURFACE WINDS WILL VARY FROM THE SOUTHEAST TO
SOUTHWEST AT 10 TO 15 KTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
SLIGHTLY COOLER...NEAR NORMAL...AFTERNOON TEMPERATURES AND HIGHER
RELATIVE HUMIDITY LEVELS ARE EXPECTED. MINIMUM RELATIVE HUMIDITY
LEVELS WILL RANGE FROM 15 TO 25 PERCENT AND RECOVER OVERNIGHT TO 35
TO 45 PERCENT. THERE WILL BE A DAILY THREAT OF AFTERNOON AND EVENING
THUNDERSTORMS...BUT THESE WILL BE MAINLY CONFINED TO THE HIGHER
TERRAIN OF SOUTH-CENTRAL ARIZONA. WINDS WILL BE GENERALLY LESS THAN
15 MPH AND PREVAIL OUT OF THE SOUTHWEST MOST AFTERNOONS AND EVENINGS.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

$$

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

DISCUSSION...MEYERS/PERCHA
AVIATION...MCLANE
FIRE WEATHER...MCLANE