Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 291726 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1025 AM PDT FRI AUG 29 2014

...UPDATED AVIATION DISCUSSION...

.SYNOPSIS...

HIGH PRESSURE WILL KEEP TEMPERATURES ABOVE NORMAL ACROSS THE REGION
THROUGH SATURDAY. GUSTY SUNDOWNER WINDS ARE EXPECTED AT TIMES
THROUGH SATURDAY NIGHT. A WEAK TROUGH AND INCREASING ONSHORE FLOW
WILL BRING GRADUAL COOLING TO THE REGION SUNDAY THROUGH MID
WEEK...WITH INCREASING NIGHT THROUGH MORNING CLOUDS IN COASTAL AND
VALLEY AREAS.

&&

.SHORT TERM (TODAY-SUN)...

NOT A LOT OF CHANGES MADE TO THE FORECAST THIS MORNING. JUST BUMPED
SOME OF THE TEMPERATURES ALONG THE CENTRAL COAST AND THE OXNARD
PLAIN DOWN A COUPLE DEGREES FOR TODAY...AS MOST COASTAL AREAS SHOULD
BE ABOUT THE SAME OR A COUPLE DEGREES COOLER TODAY WITH A SLIGHT
INCREASE IN ONSHORE GRADIENTS AND SLIGHTLY DEEPER MARINE LAYER. WITH
UPPER LEVEL HIGH PRESSURE REMAINING IN PLACE...INLAND AREAS WILL
REMAIN HOT...WITH THE DESERT AND MANY VALLEY LOCATIONS TOPPING OUT
AROUND 100 DEGREES THIS AFTERNOON. MARINE LAYER AT LAX THIS MORNING
WAS AROUND 1200 FEET DEEP...WHILE UP AT VANDENBERG...IT WAS AROUND
1800 FEET. NO COASTAL STRATUS SOUTH OF POINT CONCEPTION THIS
MORNING...OTHER THAN A FEW PATCHES OFF THE COAST. LOW CLOUDS AND FOG
ALONG THE CENTRAL COAST WILL CLEAR OUT QUICKLY THIS MORNING.

THE ONLY OTHER NOTABLE FORECAST ITEM IN THE SHORT TERM IS THE WEAK
SUNDOWNER WIND EVENT FOR TONIGHT. GUSTY NW TO N WINDS ARE EXPECTED
ACROSS THE SANTA YNEZ RANGE AND THROUGH THE I-5 CORRIDOR
TONIGHT...BUT WINDS SHOULD REMAIN BELOW ADVISORY LEVELS. THE SBA
SOUTH COAST COULD BE QUITE WARM LATER THIS AFTERNOON AND THIS
EVENING...WITH HIGHS IN THE MID 90S FOR THE FOOTHILL AREAS. AN
ADVISORY LEVEL SUNDOWNER LOOKS MORE LIKELY TOMORROW NIGHT...AS THERE
WILL BE BETTER UPPER LEVEL SUPPORT AND SLIGHTLY STRONGER NORTHERLY
GRADIENTS.

***FROM PREVIOUS DISCUSSION***

A BROAD TROUGH WILL MOVE INTO THE PAC NW TONIGHT AND SAT...FORCING
THE UPPER HIGH A BIT SOUTHWARD. THE WRF SHOWS AN EDDY CIRCULATION
TONIGHT ACROSS THE INNER WATERS...AND SHOWS STRATUS PUSHING INTO
COASTAL SECTIONS OF L.A. COUNTY AND POSSIBLY VTU COUNTY AS WELL.
FOR NOW...HAVE KEPT WIDESPREAD NIGHT THROUGH MORNING STRATUS IN
THE FORECAST ACROSS THE CENTRAL COAST AND THE SANTA YNEZ
VALLEY...ALTHOUGH IF THE 06Z WRF IS CORRECT...CLOUDS WOULD BE PATCHY
AT WORST IN THOSE AREAS. MAX TEMPS SHOULD BE COUPLE OF DEGREES LOWER
IN MOST AREAS ON SAT...AND IF THE 06Z WRF IS CORRECT...MAX TEMPS
WILL BE LOWER THAN CURRENTLY FORECAST IN THE VLYS.

AS THE AXIS OF THE BROAD TROUGH MOVES INTO THE GREAT BASIN SAT
NIGHT...SOME SUBSIDENCE WILL SPREAD INTO THE REGION...AND N-S
GRADIENTS WILL INCREASE. THIS MAY BRING SOME ADVISORY LEVEL NW TO N
WINDS TO AREAS THROUGH AND BELOW PASSES AND CANYONS OF THE SANTA
YNEZ MTNS AND ADJACENT S COAST OF SBA COUNTY...AND THROUGH THE
INTERSTATE 5 CORRIDOR SAT NIGHT. NIGHT THROUGH MORNING STRATUS
SHOULD BECOME WIDESPREAD IN COASTAL SECTIONS OF L.A. COUNTY AND
POSSIBLY VTU COUNTY...AND COULD PUSH INTO THE SAN GABRIEL VALLEY
LATE SAT NIGHT/SUN MORNING. MAX TEMPS SHOULD BE DOWN A FEW DEGREES
IN MOST AREAS ON SUNDAY AS HEIGHTS/THICKNESSES AND TEMPS AT 950 MB
ALL FALL.

.LONG TERM (MON-THU)...WEAKLY CYCLONIC WNWLY FLOW ALOFT WILL
SET UP ACROSS THE REGION MON...THEN A WEAK UPPER TROUGH WILL
APPROACH THE REGION FROM THE W ON TUE...FOLLOWED BY ANOTHER WEAK
TROUGH ON WED. THE MARINE LAYER SHOULD CONT TO DEEPEN...WITH NIGHT
THROUGH MORNING LOW CLOUDS PUSHING INTO MOST VALLEY AREAS BY MON
NIGHT/TUE MORNING. MAX TEMPS WILL BE DOWN A BIT EACH DAY MON THROUGH
WED...PROBABLY DOWN TO BELOW NORMAL LEVELS IN MOST AREAS BY TUE...
AND POSSIBLY AS EARLY AS MONDAY. THE UPPER TROUGH WILL LINGER JUST
W OF THE REGION ON THU...SO BELOW NORMAL TEMPS WILL LIKELY
CONTINUE...WITH PLENTY OF NIGHT THROUGH MORNING LOW CLOUDS AND FOG
WEST OF THE MTNS.

&&

.AVIATION...29/1725Z...

OVERALL...MODERATE CONFIDENCE IN 18Z TAF PACKAGE. VFR CONDS EXPECTED
ALL SITES THROUGH EARLY THIS EVENING. FOR TONIGHT...IFR/LIFR CIGS
EXPECTED TO RETURN TO CENTRAL COAST AND SALINAS VALLEY. FOR AREAS
SOUTH OF POINT CONCEPTION...WEAK EDDY MAY SPIN UP TONIGHT...WITH IFR
CIGS DEVELOPING AT KLGB/KLAX AND EVEN POTENTIALLY PUSHING UP TO KOXR
LATE TONIGHT.

KLAX...MODERATE CONFIDENCE IN 18Z TAF. TIMING OF IFR CIG RETURN
TONIGHT COULD BE +/- 3 HOURS OF CURRENT 08Z FORECAST.

KBUR...HIGH CONFIDENCE IN 18Z TAF. THERE IS A 10% CHANCE OF IFR/LIFR
CIGS DURING THE 10Z-16Z TIME PERIOD.

&&

.MARINE...29/830 AM...

OUTER WATERS...

FOR THE OUTER WATERS...HIGH CONFIDENCE IN THE CONTINUATION OF SMALL
CRAFT ADVISORY CONDITIONS THROUGH THE WEEKEND...AND CONTINUING INTO
EARLY NEXT WEEK. MODERATE CONFIDENCE IN GALE FORCE WINDS DEVELOPING
SATURDAY AFTERNOON/NIGHT.

FOR INNER WATERS...THE INCREASING NORTHWEST FLOW WILL PRODUCE SOME
GUSTY WINDS ACROSS THE WESTERN SECTIONS OF THE WATERS. MODERATE
CONFIDENCE IN SMALL CRAFT ADVISORY CONDITIONS ACROSS THE WESTERN
HALF OF THE SANTA BARBARA CHANNEL THIS AFTERNOON/EVENING. WITH
STRONGER SUNDOWNER WINDS EXPECTED SATURDAY EVENING...HIGHER
CONFIDENCE IN DEVELOPMENT OF SMALL CRAFT ADVISORY LEVELS ACROSS THE
WESTERN SANTA BARBARA CHANNEL.

MARIE`S SWELL EFFECT WILL CONTINUE TO SUBSIDE TODAY AND THEN LINGER
INTO SATURDAY. A SMALL TO MODERATE LONG PERIOD SWELL FROM THE
SOUTHERN HEMISPHERE IS LIKELY TO ARRIVE NEXT FRIDAY AND PERSIST
THROUGH NEXT WEEKEND.

&&

.BEACHES...29/830 AM...

THE SURF WILL CONTINUE TO SUBSIDE TODAY BUT THE RISK OF STRONG RIP
CURRENTS WILL REMAIN HIGH ALONG ALL EXPOSED SOUTH FACING SHORES. THE
SURF WILL LIKELY SUBSIDE BELOW HIGH SURF THRESHOLDS THIS EVENING.
A LOW PRESSURE SYSTEM SOUTHEAST OF NEW ZEALAND YESTERDAY AND TODAY
WITH STORM FORCE WINDS HAD GENERATED SEAS OVER 40 FEET IN AN AREA
BETWEEN 200-215 DEGREES RELATIVE TO SOUTHERN CALIFORNIA. THE SWELLS
FROM THE STORM WILL LIKELY BEGIN TO ARRIVE LATE NEXT THURSDAY OR
FRIDAY. HIGHER SURF COULD AFFECT SOUTH TO SOUTHWEST FACING
BEACHES...BUT NOTHING CLOSE TO WHAT SOUTHERN CALIFORNIA EXPERIENCED
OVER THE PAST FEW DAYS.

&&

.FIRE WEATHER...29/1015 AM.
GUSTY SUNDOWNER WINDS ARE EXPECTED ACROSS THE PASSES AND
CANYONS OF SOUTHERN SANTA BARBARA COUNTY FROM THE LATE AFTERNOON
THROUGH NIGHTTIME HOURS THROUGH SATURDAY NIGHT. WIND GUSTS ARE
EXPECTED TO RANGE BETWEEN 30 AND 40 MPH WITH TONIGHT`S EVENT...MOSTLY
FOCUSED ACROSS WESTERN PORTIONS OF THE SOUTH COAST. TOMORROW NIGHT`S EVENT
IS EXPECTED TO BE SLIGHTLY STRONGER AND MORE WIDESPREAD. WIND EXPOSED
LOCATIONS AND FOOTHILLS WILL GENERALLY SEE HUMIDITIES IN THE TEENS
WITH TEMPERATURES CLIMBING TO 90 DEGREES OR ABOVE. THE COMBINATION OF
GUSTY SUNDOWNER WINDS...LOW HUMIDITIES...AND WARM TEMPERATURES WILL
BRING ELEVATED FIRE DANGER TO THE SANTA BARBARA SOUTH COAST AND ADJACENT
FOOTHILLS THROUGH SATURDAY NIGHT...WITH BRIEF PERIODS OF CRITICAL FIRE
WEATHER CONDITIONS EACH NIGHT. GUSTY NORTHWEST WINDS AND LOW HUMIDITIES
WILL ALSO IMPACT THE INTERSTATE 5 CORRIDOR OF THE LOS ANGELES COUNTY
MOUNTAINS AND ANTELOPE VALLEY THROUGH SATURDAY NIGHT. THE STRONGEST
WINDS FOR THESE AREAS ARE EXPECTED LATE SATURDAY AFTERNOON THROUGH
SATURDAY NIGHT...WHEN GUSTS BETWEEN 35 AND 45 MPH CAN BE EXPECTED.


&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
GALE WATCH (SEE LAXMWWLOX).

&&

$$

PUBLIC...SS/DB
AVIATION...RAT
MARINE...RAT
FIRE...GOMBERG
SYNOPSIS...DB

WWW.WEATHER.GOV/LOSANGELES




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