Weather Service Report


293 
FXUS66 KLOX 260133
AFDLOX

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

...UPDATED AVIATION DISCUSSION...

.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 NOTICEABLE 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...26/0130Z...

THE BASE OF THE INVERSION AT KLAX AT 1655Z WAS NEAR 700 FT. THE 
INVERSION TOP WAS AT 1600 FEET WITH A TEMPERATURE OF 22 DEGREES C.

NORTH OF POINT CONCEPTION...A WEAK COLD FRONT WAS MOVING THROUGH THE 
AREA WITH ONLY ISOLATED LIGHT SHOWERS ACROSS THE NE PORTION OF SLO 
COUNTY. SHOWER CHANCES WILL END BY 03Z. AFTER 03Z VFR CONDS EXPECTED 
TO PREVAIL EXCEPT FOR KPRB WHERE MVFR CIGS MAY DEVELOP AGAIN LATE 
TONIGHT. 

SOUTH OF POINT CONCEPTION...FOR THIS EVENING...VFR CONDS SHOULD 
PREVAIL WITH A FEW HIGH CLOUDS AND NO CHANCE OF SHOWERS...EXCEPT 
NORTHERN SLOPES OF LA/VTU COUNTY MTNS. HOWEVER...MODERATE CONFIDENCE 
IN THE RETURN OF SOME MVFR/IFR CIGS TO LAX BASIN TAF SITES AFTER 08Z.

KLAX...HIGH CONFIDENCE IN 00Z TAF THROUGH 06Z WITH VFR CONDS AFTER 
06Z...LOWER CONFIDENCE IN RETURN OF STRATUS CIGS WITH TIMING AND 
HEIGHT OF CIGS UNCERTAIN. 

KBUR...MODERATE CONFIDENCE IN 00Z TAF. 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...CK
MARINE...SMITH
SYNOPSIS...SWEET

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