Area Forecast Discussion
Issued by NWS Phoenix, AZ

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KPSR 271637
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
935 AM MST THU NOV 27 2014


.SYNOPSIS...
A WARM AND DRY STRETCH OF WEATHER WILL AFFECT THE REGION THROUGH THE
UPCOMING WEEKEND UNDER HIGH PRESSURE ALOFT. HIGH TEMPERATURES WILL
BE THE WARMEST TODAY...PEAKING IN THE UPPER LOWER 80S... AND THEN
SLOWLY COOL THROUGH EARLY NEXT WEEK WHILE STILL REMAINING WELL ABOVE
SEASONAL NORMALS. A LOW PRESSURE SYSTEM EXPECTED FOR EARLY OR MID
NEXT WEEK WILL BRING CHANCES FOR RAIN AND COOLER TEMPERATURES.

&&

.DISCUSSION...
CLEAR SKIES ACROSS THE FORECAST AREA THIS MORNING WITH HIGH PRESSURE
IN CHARGE OVER THE SOUTHWEST STATES. SURFACE HIGH PRESSURE CENTERED
OVER COLORADO AND LOWER PRESSURE OVER THE GULF OF CALIFORNIA IS
CREATING A NORTHEASTERLY ORIENTED GRADIENT. THIS WILL LEAD TO
NORTHEAST AND EAST WIND DIRECTIONS TODAY AND POSSIBLY SOME LOCALIZED
BREEZINESS...MORE NOTICEABLY EAST OF THE LOWER COLORADO RIVER
VALLEY. 12Z SOUNDINGS IN/NEAR ARIZONA INDICATE SOME ADDITIONAL
WARMTH IN THE LOWER LEVELS YET TO MAKE IT TO THE SURFACE. THIS WILL
ENABLE ANOTHER INCREASE IN HIGH TEMPERATURES TODAY. LOCATIONS THAT
SEE MORE WIND WILL LIKELY SEE MORE WARMING. TEMPERATURE GUIDANCE
FAIRLY INSISTENT ON LOW 80S FOR MUCH OF THE LOWER DESERTS INCLUDING
PHOENIX METRO. MAY NUDGE HIGHS DOWN A DEGREE OR SO AS MIXING IS
HARDER TO COME BY THIS TIME OF YEAR. OTHERWISE...ABOVE NORMAL HIGH
TEMPERATURES CONTINUE THROUGH THE WEEKEND.

&&

.PREVIOUS DISCUSSION ISSUED 314 AM MST/214 AM PST...
ANOTHER QUIET DAY UNDER CLEAR SKIES IS IN STORE FOR TODAY...BUT WITH
MUCH WARMER TEMPERATURES. HIGHS FOR TODAY SHOULD BREAK 80 DEGREES IN
MOST LOWER DESERT LOCATIONS WHICH IS AROUND 10 DEGREES ABOVE NORMAL.
THE PACIFIC RIDGE OF HIGH PRESSURE IN PLACE OVER THE WESTERN UNITED
STATES BRINGING THE WARM CONDITIONS WILL PERSIST INTO THE COMING
WEEKEND...BUT GRADUALLY FLATTEN OUT AS AN UPSTREAM TROUGH DIGS INTO
THE PACIFIC NORTHWEST LATE FRIDAY INTO SATURDAY. 500MB HEIGHTS OF
572-576DM STARTING FRIDAY AND LIKELY LASTING INTO EARLY NEXT WEEK
WILL PROVIDE FOR CONTINUED ABOVE NORMAL TEMPERATURES ACROSS THE
REGION. EXPECTING TO SEE SOME GRADUAL COOLING AFTER TODAY...BUT
LOWER DESERT HIGHS IN THE MID TO UPPER 70S SHOULD PERSIST AT LEAST
THROUGH NEXT MONDAY.

A MUCH MORE COMPLEX SYNOPTIC PATTERN IS IN STORE FOR THE EASTERN
PACIFIC AND WESTERN UNITED STATES FOR NEXT WEEK AS MODELS CONTINUE
TO ADVERTISE A DEEP CUT-OFF LOW OVER THE EASTERN PACIFIC FOR EARLY
NEXT WEEK. OVERALL...LONG RANGE MODELS AGREE THERE WILL BE A STRONG
POLAR JET DIGGING SOUTHWARD THIS WEEKEND ACROSS THE EASTERN PACIFIC
GIVING RISE TO A DEEP CLOSED LOW BY SUNDAY NIGHT INTO MONDAY. THIS
DEEP LOW SITUATED WELL OFF THE CALIFORNIA COAST LOOKS LIKE IT WILL
ALSO INTERACT WITH A STRENGTHENING SUB-TROPICAL JET AND MOISTURE
FEED. BEYOND MONDAY...MODELS DISAGREE WITH THE EVOLUTION OF THE LOW
AND HOW MUCH MOISTURE WILL EVENTUALLY MAKE ITS WAY INTO THE DESERT
SOUTHWEST VIA THE SUB-TROPICAL JET.

BEST RAIN CHANCES FOR OUR REGION STILL LOOKS TO BE LATER TUESDAY
INTO EARLY WEDNESDAY MOST LIKELY RESULTING FROM THE POTENTIAL STRONG
MOISTURE SURGE FROM THE SUB-TROPICAL JET INFLUENCE AND BROAD BUT
WEAK ASCENT ALOFT. THE LAST FEW MODEL RUNS HAVE TRENDED TOWARD A
SLOWER EVOLUTION OF THE LOW AND A BIT DRIER SOLUTION. THE
OPERATIONAL GFS AND GFS ENSEMBLE GENERALLY POINTS TOWARD A STRONGER
MOISTURE FEED AND BETTER RAIN CHANCES STARTING SOMETIME TUESDAY AND
LIKELY ENDING EARLY WEDNESDAY. THE EUROPEAN HAS BEEN TRENDING TOWARD
A DRIER OR EVEN COMPLETELY DRY SOLUTION...KEEPING THE CLOSED LOW
FURTHER OFF THE COAST WHILE ALSO BRINGING MUCH LESS MOISTURE
NORTHWARD. GIVEN THE OVERALL DRYING TREND...HAVE TRIMMED POPS
SLIGHTLY FOR TUESDAY AND WEDNESDAY...BUT KEPT SLIGHT CHANCE AND
CHANCE POPS FAIRLY WIDESPREAD ACROSS THE CWA. TEMPERATURES HAVE BEEN
EDGED HIGHER TO SLIGHTLY ABOVE NORMAL VALUES THROUGH THE MIDDLE OF
NEXT WEEK.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...INCLUDING KIPL AND
KBLH...

UPPER LEVEL RIDGE OVER THE DESERT SOUTHWEST WILL ALLOW FOR MOSTLY
CLEAR SKIES AND LIGHT WINDS AT ALL TERMINALS THROUGH AT LEAST
FRIDAY. WINDS WILL FAVOR TYPICAL DIURNAL TRENDS AT ALL
SITES...GENERALLY 5 KTS OR LESS. REGARDING THE MULCH FIRE NEAR LUKE
AIR FORCE BASE...THIS SHOULD ONLY HAVE AN IMPACT ON SLANT VSBYS AS
WINDS SHOULD BE TOO LIGHT TO CARRY DENSE SMOKE TO ANY OF THE MAIN
PHOENIX TERMINALS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH MONDAY...RESULTING IN A
CONTINUED PERIOD OF MOSTLY CLEAR SKIES AND DRY CONDITIONS. SINGLE
DIGIT HUMIDITIES WITH FAIR OVERNIGHT RECOVERIES WILL BE COMMON
THROUGH THE WEEKEND. STILL MONITORING THE POTENTIAL FOR A LARGE
UPPER LEVEL STORM SYSTEM TO MOVE THROUGH THE AREA BY THE MIDDLE OF
NEXT WEEK. SOME MODEL DIFFERENCES HAVE BECOME MORE AND MORE EVIDENT
OVER THE PAST FEW RUNS...THUS CONFIDENCE IN EXACTLY HOW THE FORECAST
WILL EVOLVE NEXT WEEK IS LOW. STILL HANGING ONTO THE IDEA OF
INCREASING RAIN CHANCES AND ELEVATED HUMIDITIES BY
TUESDAY/WEDNESDAY.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

$$

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

DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN
AVIATION...LEINS
FIRE WEATHER...LEINS





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.