Area Forecast Discussion
Issued by NWS Phoenix, AZ

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014
FXUS65 KPSR 081137 AAA
AFDPSR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
435 AM MST MON FEB 8 2016

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.

&&

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE OVER THE
SOUTHWESTERN UNITED STATES THROUGH THE COMING WORK WEEK. THIS WILL
RESULT IN A PROLONGED PERIOD OF SUNNY SKIES AND ABOVE NORMAL
TEMPERATURES ALONG WITH RELATIVELY LIGHT WINDS.

&&

.DISCUSSION...

UPPER RIDGE HEIGHTS ENCOMPASS THE WESTERN MAJORITY OF THE NORTH
AMERICAN CONTINENT...SPANNING FAR TO THE NORTH INTO YUKON AND NW
TERRITORIES AS WELL AS AK. MEANWHILE...GENERAL AREA OF WEAK/LOWER
HEIGHTS CONTINUES TO PERSIST WEST OF AND OVER THE BAJA PENINSULA IN
CONJUNCTION WITH AN UL CIRC CENTER BEST OBSERVED VIA 400MB AND ABOVE
STREAMLINES. CLOUD COVER REMAINS CONFINED TO LOCATIONS JUST ALONG AND
SOUTH OF THE INTERNATIONAL BORDER AT TIME OF THIS WRITING...WITH
CLEAR SKIES AND MILD OVERNIGHT TEMPS OBSERVED ACROSS THE CWA.

FORECAST FOR THIS WORK WEEK WILL BE ONE OF PERSISTENCE...WITH
DAYTIME HIGHS PEAKING INTO THE 80S FOR MANY LOWER DESERT SITES AND
OVERALL DRY CONDITIONS. THE FORECAST AREA WILL GENERALLY REMAIN ON
THE EASTERN FLANK OF THE STRONG WEST COAST RIDGE...WITH 1000-500MB
THICKNESSES PEAKING INTO THE MID 560DM RANGE AND 850MB TEMPERATURES
RANGING 14 TO 16C EACH AFTERNOON WITH FAIRLY GOOD MIXING. THIS
ORIENTATION OF THE RIDGE WILL ALSO LEAD TO PROLONGED PERIODS OF
EASTERLY RIDGETOP/GAP WINDS OVER THE HIGHER TERRAIN NORTH/EAST OF
PHOENIX AND NORTHERLY WINDS DOWN THE CO RIVER VALLEY. FCST ML/UL WIND
STREAMLINES INDICATE THE RIDGE CIRC CENTER...CURRENTLY ANALYZED OVER
CA/OR...TO SINK SOUTHWARD THROUGH THE GREAT BASIN AND OVER SOCAL
DURING THE WEEK. THIS MOTION WILL SHUNT THE AFOREMENTIONED WEAK
ML/UL LOW ANCHORED SLIGHTLY OVER BAJA CA AND ASSOCIATED SUBTROPICAL
JET STREAM OFF TO OUR SE. WESTERN RIDGE HEIGHTS RANK IN THE 99TH
PERCENTILE TO MAX RANGE ON NAEFS PERCENTILE TABLES AND FORECAST HIGHS
REFLECT THE ANOMALOUS WARMTH AS WELL. A FEW RECORDS COULD BE AT
STAKE...MOSTLY IN PHOENIX...DURING THE WORK WEEK. PLEASE REFERENCE
THE CLIMATE SECTION BELOW FOR THE FCST VALUES AND RECORD DATA.

EXTENDED PERIOD...
DETERMINISTIC AND ENSEMBLE FCST SOLNS ARE IN EXCELLENT AGREEMENT
THROUGH THE LATE WEEKEND...CONTINUING OUR WARM AND DRY FORECAST UNDER
A WEST COAST RIDGE. RIDGE HEIGHTS DO BECOME MODIFIED DURING THE END
OF THE WEEK AS A PACIFIC SHORTWAVE RIDES UP INTO THE PAC NW.
PHASING AND SOLN DIFFERENCES BEGIN TO CROP UP BEGINNING MON
15/00Z /SUNDAY NIGHT/. DIFFERENCES LIE BETWEEN THE RESOLUTION AND
DEPTH OF SHORTWAVE MOVEMENT OVER THE NORTH CENTRAL CONUS AS WELL AS
CONVECTION OVER THE EQUATORIAL PACIFIC/EL NINO REGION. GFS/GEFS
SOLNS MAINTAIN TROPOSPHERIC WEAKNESS WILL BE STRONGER OVER THE
EASTERN PACIFIC SUCH THAT SHORTWAVE ENERGY WILL CUT OFF AND INTERACT
WITH ANOTHER EAST PAC/BAJA LOW AND BRING SOME MOISTURE INTO THE
REGION BY EARLY NEXT WEEK. MEANWHILE...EC/GEM/NAEFS SOLNS ARE NOT AS
ENTHUSIASTIC...MAINTAINING RIDGE HEIGHTS AND DRY CONDITIONS OVER THE
CWA. THE ONE UPSIDE AMONG THESE DIFFERENCES WILL BE A SLIGHT
LOWERING OF UL HEIGHTS...WITH A SUBTLE SCALING BACK THE WARMTH FROM
THE WORK WEEK FOR THE WEEKEND.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL

STRONG SFC HIGH PRESSURE OVER THE 4-CORNERS REGION TO KEEP WINDS
FROM AN EASTERLY DIRECTION THROUGH THE TAF PERIOD AT ALL OF THE PHX
AREA TERMINALS. WIND SPEEDS ARE EXPECTED TO REMAIN ON THE LIGHT
SIDE...MAINLY 8 KTS OR LESS THROUGH MID-MORNING TODAY. WINDS WILL
THEN BECOME A BIT STRONGER...IN THE 8-12 KT RANGE DURING THE LATE
MORNING AND EARLY AFTERNOON HOURS BEFORE DROPPING BACK AOB
8 KTS DURING THE LATE AFTERNOON AND EVENING HOURS. ALTHOUGH STRONGER
EASTERLY WINDS WILL LIKELY DEVELOP LATE TONIGHT AND EARLY MONDAY
BETWEEN 1-2 KFT AGL...IN THE 15-20 KT RANGE...THEY ARE EXPECTED TO
REMAIN JUST BELOW LLWS CRITERIA. CLEAR SKIES WITH JUST A FEW HIGH
CIRRUS CLOUDS PASSING OVERHEAD FROM TIME-TO-TIME TO PREVAIL THROUGH
THE TAF PERIOD.

NOTE...AT KPHX...WINDS MAY TEND TOWARDS LIGHT/VARIABLE OR EVEN LIGHT
SOUTHWEST FOR A FEW HOURS THIS MORNING BEFORE THE STRONGER LOW LEVEL
NELY WINDS MIX TO THE SURFACE...TYPICALLY BY 16-17Z.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LIGHT NORTHERLY WINDS AT KBLH AND LIGHT NORTHWESTERLY WINDS (AOB
6KTS) AT KIPL TO PREVAIL THROUGH MIDDAY TODAY WITH SOMEWHAT STRONGER
WINDS (10-12 KTS) DEVELOPING IN THE AFTERNOON AS SFC HIGH PRESSURE
STRENGTHENS OVER CENTRAL/SOUTHERN NV. CLEAR SKIES WITH JUST A FEW
HIGH CIRRUS CLOUDS PASSING OVERHEAD FROM TIME-TO-TIME TO PREVAIL
THROUGH THE TAF PERIOD.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

WEDNESDAY THROUGH SUNDAY...AN UNSEASONABLY STRONG HIGH PRESSURE
RIDGE WILL BUILD OVER THE WESTERN STATES DURING THE WEEK. THIS WILL
LEAD TO A PERSISTENT PERIOD OF WELL ABOVE NORMALS HIGH EMPERATURES
...WITH READINGS PEAKING 10 TO 15 DEGREES ABOVE SEASONAL NORMALS.
MANY LOWER ELEVATION AND DESERT SITES WILL SEE A STRETCH OF DAYS
WITH HIGH TEMPERATURES WARMING PAST THE 80 DEGREE MARK. RH`S WILL
ALSO REMAIN ON THE DRIER AND BELOW NORMAL SIDE DURING THE WEEK WITH
MIN VALUES TYPICALLY IN THE LOW TO MIDDLE TEENS.

LOCALLY BREEZY CONDITIONS ALONG THE CO RIVER VALLEY ARE EXPECTED
EACH AFTERNOON. MORE NOTICEABLE EASTERLY WINDS WILL FLOW INTO THE
SOUTH-CENTRAL AZ DESERTS...WITH ELEVATED WINDS OVER RIDGETOPS AND
GAPS TO THE NORTH/EAST OF PHOENIX. WINDS ELSEWHERE WILL GENERALLY
FOLLOW TYPICAL DRAINAGE/SLOPE DRIVEN HEADINGS WITH LIGHT SPEEDS. BY
WEEKS END THE UPPER RIDGE WILL BEGIN TO SHIFT TO OUR EAST AS
TROUGHING ALIGNS ITSELF OVER THE WEST COAST AGAIN. SOME VERY SLIGHT
TEMPERATURE COOLING AND INCREASING CLOUDINESS ARE LIKELY OVER THE
WEEKEND.

&&

.CLIMATE...
                   PHOENIX         |        YUMA
             FCST | RECORD (YEAR)  | FCST | RECORD (YEAR)

MON FEB 8      83 | 86 (1970)      | 81 | 88 (1996)
TUE FEB 9      83 | 84 (1987)      | 83 | 90 (2015)
WED FEB 10     83 | 87 (1951)      | 83 | 93 (1951)
THU FEB 11     83 | 83 (1951)      | 84 | 86 (1971)

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

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

DISCUSSION...NOLTE
AVIATION...PERCHA/CB
FIRE WEATHER...NOLTE/CB



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