Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 252155
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
253 PM PDT SAT OCT 25 2014

.SYNOPSIS...

RESIDUAL MOISTURE WILL BRING SLIGHT CHANCE OF SHOWERS ON NORTHERN
MOUNTAIN SLOPES INTO SUNDAY MORNING. THERE WILL BE SOME GUSTY WINDS
TONIGHT THROUGH EARLY MONDAY IN THE SANTA YNEZ MOUNTAINS AND THROUGH
THE INTERSTATE 5 CORRIDOR. IT WILL BE COOLER THIS WEEKEND AND EARLY
NEXT WEEK. A WARMING TREND WILL BEGIN TUESDAY...WITH ABOVE NORMAL
DAYTIME TEMPERATURES THROUGH THURSDAY.

&&

.SHORT TERM (TODAY-TUE)...

SATELLITE IMAGERY CONTINUES TO SHOW THE DYING COLD FRONT PUSHING
INTO SLO AND SBA COUNTIES THIS AFTERNOON. SO FAR ALL REPORTS OF
MEASURABLE RAINFALL HAVE STAYED NORTH OF SLO COUNTY. THAT WILL
PROBABLY CONTINUE TO BE THE CASE FOR THE CENTRAL COAST THIS
EVENING...WITH MOST LOCATIONS SEEING NO MORE THAN A FEW SPRINKLES.

AHEAD OF THE FRONT...THERE WILL CONTINUE TO BE SOME GUSTY
SUB-ADVISORY WINDS OUT OF THE SW ACROSS THE VENTURA AND LA COUNTY
MOUNTAINS. AFTER THE FRONT GOES THROUGH...WINDS WILL SHIFT TO NW
LATER TONIGHT. THIS COULD RESULT IN SOME LIGHT SHOWERS ON THE NORTH
FACING SLOPES IN THE NORTHERN VENTURA AND LA COUNTY MOUNTAINS
THROUGH EARLY SUNDAY MORNING. FORECAST ALSO CALLS FOR SOME LOW
CLOUDS TO DEVELOP OVER THE LA COAST AND VALLEYS BY EARLY SUNDAY
MORNING...WHILE THE CENTRAL COAST STAYS MOSTLY CLOUD FREE BEHIND THE
FRONT. HOWEVER...CONFIDENCE IN THE LOW CLOUD FORECAST IS RATHER LOW
WITH THE FRONT MOVING THROUGH.

HIGH TEMPS WILL BE A FEW DEGREES COOLER ON SUNDAY AS THE COOL
AIRMASS BEHIND THE FRONT MOVES INTO PLACE. WITH NW FLOW ALOFT AND A
TIGHTENING NORTHERLY SURFACE PRESSURE GRADIENT...SUNDOWNER WINDS ARE
EXPECTED ALONG THE SANTA YNEZ RANGE AND THROUGH THE I-5 CORRIDOR
BOTH SUNDAY AND MONDAY NIGHT. HOWEVER...LATEST RUNS NAM DO NOT HAVE
MUCH IN THE WAY OF UPPER-LEVEL SUPPORT...SO A WIND ADVISORY DOES NOT
APPEAR NECESSARY AT THIS TIME.

BY MONDAY MORNING...SOME WEAK OFFSHORE FLOW IS EXPECTED SO MONDAY
COULD BE A COUPLE DEGREES WARMER THAN SUNDAY...BUT NOT A WHOLE LOT
OF CHANGE EXPECTED WITH A NW FLOW PATTERN ALOFT. WITH CONTINUED WEAK
OFFSHORE FLOW ON TUESDAY AND HIGH PRESSURE STARTING TO DEVELOP
ALOFT...MORE NOTICABLE WARMING IS LIKELY FOR TUESDAY. HIGHS TUESDAY
SHOULD CLIMB BACK INTO THE LOW 80S FOR THE VALLEYS AND MID 70S FOR THE
COAST. SKIES SHOULD REMAIN MOSTLY CLEAR ON MONDAY AND TUESDAY AS
WELL...WITH THE WEAK OFFSHORE FLOW.

.LONG TERM (WED-SAT)...

THE WARMING TREND AND MOSTLY CLEAR SKIES WILL LIKELY CONTINUE
THROUGH WEDNESDAY WITH WEAK OFFSHORE FLOW DURING THE MORNING HOURS
AND HIGH PRESSURE CONTINUING TO BUILD. EXPECT HIGHS IN THE MID-UPPER
80S FOR THE VALLEYS ON WEDNESDAY AND NEAR 80 FOR THE COAST. SLIGHT
COOLING IS LIKELY FOR THURSDAY AS OFFSHORE FLOW WEAKENS AND THE
UPPER-LEVEL RIDGE AXIS MOVES EAST OF THE AREA. THE 12Z GFS, ECMWF,
AND GEM REMAIN IN FAIRLY GOOD AGREEMENT THAT A LARGE TROUGH WILL
APPROACH THE WEST COAST ON FRIDAY OR SATURDAY...BRINGING THE
POSSIBILITY OF SOME RAIN TO MOST OF THE AREA. FOR NOW...PLAYED IT
SAFE AND ADDED A SLIGHT CHANCE OF SHOWERS N OF PT CONCEPTION FOR
LATE FRIDAY AND SATURDAY...ALTHOUGH IF THE CURRENT MODEL PROJECTIONS
COME TRUE...VENTURA AND LA COUNTY WOULD SEE SOME LIGHT RAINFALL
AMOUNTS AS WELL.

&&

.AVIATION...25/1800Z...

THE BASE OF THE INVERSION AT KLAX AT 1655Z WAS NEAR 640 FT. THE
INVERSION TOP WAS AT 2600 FEET WITH A TEMPERATURE OF 21 DEGREES C.

NORTH OF POINT CONCEPTION...A WEAK COLD FRONT WILL BRING ISOLATED
LIGHT SHOWERS TO THE AREA THIS AFTERNOON INTO EARLY EVENING WITH A
CHANCE OF MVFR CIGS. AFTER 03Z VFR CONDS EXPECTED TO PREVAIL EXCEPT
FOR KPRB WHERE MVFR CIGS MAY DEVELOP AGAIN LATE TONIGHT.

SOUTH OF POINT CONCEPTION...FOR THIS AFTERNOON AND EVENING...VFR
CONDS SHOULD PREVAIL WITH HIGH CLOUDS AND LITTLE OR NO CHANCE OF
SHOWERS. HOWEVER...MODERATE CONFIDENCE IN THE RETURN OF SOME
MVFR/IFR CIGS TO LAX BASIN TAF SITES AFTER 06Z.

KLAX...MODERATE CONFIDENCE IN 18Z TAF. VFR CONDS VIRTUALLY CERTAIN
THROUGH 06Z. AFTER 06Z...LOWER CONFIDENCE IN RETURN OF STRATUS CIGS
WITH TIMING AND HEIGHT OF CIGS UNCERTAIN.

KBUR...LOW TO MODERATE CONFIDENCE IN 18Z TAF. HIGH CLOUDS WITH VFR
CONDS THROUGH THIS EVENING. AFTER 06Z...LOW CONFIDENCE IN FORECAST
OF STRATUS CLOUDS FORMING. 40% CHANCE NO LOW CIGS WILL DEVELOP AND
TIMING/HEIGHT OF CIGS IS UNCERTAIN.

&&

.MARINE...25/200 PM...

OUTER WATERS...A WEAK FRONT IS CROSSING THE NORTHERN WATERS THIS
AFTERNOON...AND WILL MOVE INLAND SOUTH OF PT CONCEPTION TONIGHT.
HIGH CONFIDENCE IN NORTHWEST WINDS INCREASING ACROSS THE OUTER
WATERS BEHIND THE FRONT...WITH GALE FORCE GUSTS LIKELY BY SUNDAY
AFTERNOON. THE HIGHEST CONFIDENCE IN GALES IS OVER THE WATERS FROM
PT CONCEPTION TO SAN NICOLAS ISLAND...WHERE GUSTS OF 35 TO 40 KNOTS
ARE EXPECTED. IN ADDITION...A LARGE MODERATE PERIOD WEST-NW SWELL
WILL MOVE INTO THE WATERS THIS EVENING...WITH SEAS OVER THE OUTER
WATERS RISING TO 10 TO 13 FEET AT 13 SECONDS TONIGHT INTO SUNDAY.
ROUGH SEAS ARE CERTAIN DUE TO THE COMBINATION OF LARGER WEST SWELL
AND NORTHWEST WIND WAVES. WINDS WILL DIMINISH SOME BY MONDAY
MORNING...BUT SOLID SMALL CRAFT WINDS ARE LIKELY TO PERSIST OVER THE
OUTER WATERS THROUGH TUE...WITH GALE FORCE GUSTS POSSIBLE AGAIN
MONDAY NIGHT.

INNER WATERS...LARGE SEAS ARE EXPECTED IN THE NEAR-SHORE WATERS
NORTH OF PT SAL...AND A SMALL CRAFT FOR HAZARDOUS SEAS IS IN EFFECT
THIS EVENING THROUGH SUNDAY. HAZARDOUS BAR CONDITIONS WILL BE
POSSIBLE AT THE MORRO BAY ENTRANCE LATE TONIGHT. THE SOUTHERN INNER
WATERS WILL LIKELY SEE LOCAL SCA GUSTS TO 25 KT...WITH COMBINED SEAS
PEAKING NEAR 5 TO 8 FEET SUNDAY. THERE IS A 40% CHANCE THAT GUSTS
WILL BECOME WIDESPREAD ENOUGH OVER THE WESTERN PORTION OF PZZ650 AND
PZZ655 TO REQUIRE ISSUANCE OF A SMALL CRAFT ADVISORY SUNDAY
AFTERNOON/EVENING.

&&

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

&&

$$

PUBLIC...SUKUP
AVIATION/MARINE...SMITH
SYNOPSIS...SWEET

WWW.WEATHER.GOV/LOSANGELES





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