Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 290610
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1040 PM PDT SAT MAR 28 2015

AVIATION DISCUSSION UPDATED

.SYNOPSIS...

A GRADUAL COOLING TREND WILL CONTINUE INTO EARLY NEXT WEEK AS
ONSHORE FLOW CONTINUES. NIGHT THROUGH MORNING LOW CLOUDS AND FOG
WILL BE POSSIBLE ALONG THE COASTAL PLAIN. GUSTY NORTHWEST TO NORTH
WINDS WILL AFFECT PARTS OF THE AREA AROUND MID WEEK AS SEVERAL
MOISTURE STARVED FRONTS PASS TO THE NORTH. WELL ABOVE NORMAL
TEMPERATURES ARE POSSIBLE LATE NEXT WEEK AS SANTA ANA WINDS MAY
DEVELOP.

&&

.SHORT TERM (TONIGHT-TUE)...FAIR SKIES WITH A FEW HI CLOUDS WERE
NOTED ACROSS THE FORECAST AREA THIS EVENING. AN EDDY IS FORECAST TO
DEVELOP OVER THE SOCAL BIGHT LATER THIS EVENING AND SPREAD LOW
CLOUDS INTO THE L.A. COUNTY COAST BY MIDNIGHT THEN UP THE COAST TO
VTU COUNTY LATER TONIGHT...AND POSSIBLY TO THE SBA S COAST BY EARLY
SUN MORNING. PATCHY DENSE FOG WILL ALSO BE POSSIBLE. LOW LEVEL
OFFSHORE FLOW SHOULD DEVELOP ALONG THE CENTRAL COAST OVERNIGHT WHICH
SHOULD KEEP ANY LOW CLOUDS FROM FORMING THERE. OVERALL...IT LOOKS
LIKE MOSTLY CLEAR SKIES WITH A FEW HI CLOUDS WILL PREVAIL ACROSS
MOST OF THE REGION THRU THE NIGHT.

A WEAK UPPER LEVEL TROF JUST OFF THE CENTRAL CA COAST THIS EVENING
WILL DRIFT SE OVERNIGHT AND INTO THE SLO/SBA COUNTY CENTRAL COAST
SUN MORNING. WEAK UPPER TROFFINESS WILL THEN LINGER OVER THE
FORECAST AREA THRU SUN NIGHT. UPPER LEVEL RIDGING WILL BUILD INTO
THE AREA MON AND MON NIGHT...THEN WEAKEN ON ON TUE...WITH A BROAD
WLY FLOW ALOFT OVER SRN CA. LOW CLOUDS FOR COASTAL L.A./VTU/S SBA
COUNTIES SUN MORNING WILL BURN OFF BY LATE MORNING. VARYING AMOUNTS
OF MARINE LAYER CLOUDS AND FOG ARE EXPECTED NIGHT AND MORNING HOURS
FOR THE COAST AND ADJACENT VLYS S OF POINT CONCEPTION SUN NIGHT THRU
TUE MORNING...AND FOR THE CENTRAL COAST MON NIGHT INTO TUE MORNING.
SOME LOW CLOUDS WILL ALSO BE POSSIBLE BY TUE MORNING IN THE SALINAS
RIVER VALLEY. OTHERWISE...MOSTLY CLEAR SKIES WITH JUST A FEW HI
CLOUDS AT TIMES CAN BE EXPECTED OVER SWRN CA SUN THRU TUE. THE 00Z
NAM WAS FORECASTING SOME OFFSHORE LOW LEVEL FLOW FOR SLO/SBA
COUNTIES AND THE VTU INTERIOR AREAS DURING THE NIGHT AND MORNING
HOURS THRU TUE. INCREASING NW FLOW WILL AFFECT THE L.A. COUNTY MTNS
MON NIGHT AND TUE...WITH GUSTY NW WINDS ALONG THE I-5 CORRIDOR BY
LATE TUE. GUSTY W WINDS SHOULD ALSO AFFECT THE ANTELOPE VLY TUE
AFTERNOON. TEMPS ARE FORECAST TO BE SEVERAL DEGREES ABOVE NORMAL SUN
THRU TUE...WITH SUN AND MON THE WARMEST DAYS OVERALL DURING THE
PERIOD.

***FROM PREVIOUS DISCUSSION***

.LONG TERM (TUE NIGHT-SAT)...

INCREASING WESTERLY FLOW ALOFT WILL DEVELOP AN BRING A SERIES OF
WEAK DISTURBANCES ACROSS THE AREA BETWEEN WEDNESDAY AND THURSDAY.
MODELS SOLUTIONS DEVELOP A NORTHERLY GRADIENTS ACROSS THE STATE.
TEMPERATURES HAVE BEEN NUDGED COOLER FOR THE PERIOD...EXCEPT FOR THE
SANTA BARBARA SOUTH COAST WHERE COMPRESSIONAL HEATING WILL TAKE
PLACE IN SUNDOWNER WINDS. SUNDOWNER WINDS WILL DEVELOP EACH
AFTERNOON AND EVENING BETWEEN TUESDAY EVENING AND THURSDAY
NIGHT...POSSIBLY REACHING ADVISORY LEVELS. WINDS THROUGH THE
INTERSTATE 5 CORRIDOR WILL LIKELY DEVELOP...AS WELL. GFS SOLUTIONS
DO INDICATE A PERIOD WHERE WINDS COULD DEVELOP AND GFS MOS GUIDANCE
AT KSDB SUPPORT THIS WITH 20 TO 25 KNOT SUSTAINED BETWEEN TUESDAY
NIGHT AND THURSDAY NIGHT.

THE FLOW TURNS OFFSHORE BETWEEN THURSDAY NIGHT AND FRIDAY...POSSIBLY
BRINGING A BRIEF SANTA ANA WIND EVENT TO THE AREA. TEMPERATURES
HAVE BEEN LEFT UNCHANGED FOR FRIDAY BUT WINDS COULD BE UNDERDONE
FOR THURSDAY NIGHT AND FRIDAY MORNING. THE FLOW TURNS SHOULD ONSHORE
BY SATURDAY AS ANOTHER TROUGH OF LOW PRESSURE APPROACHES THE WEST
COAST.

&&

.AVIATION...29/06Z.

AT 0525Z AT KLAX... THE INVERSION WAS 2300 FEET DEEP OFF THE SURFACE
WITH A TEMPERATURE OF 22 DEGREES CELSIUS AT THE TOP.

OVERALL... LOW TO MODERATE CONFIDENCE IN THE 06Z TAFS AT COASTAL AND
ADJACENT SITES AND MODERATE TO HIGH CONFIDENCE ELSEWHERE.  THE REDUCED
CONFIDENCE ALONG THE COAST AND ADJACENT LOCATIONS IS DUE TO THE
UNCERTAINTY REGARDS THE INTENSITY... TIMING... AND LOCATION OF THE
MARINE INVERSION.  THE REDUCED CONFIDENCE ELSEWHERE IS DUE TO THE
UNCERTAINTY OF EARLY MORNING LOW CLOUDS AND FOG PRIMARILY AT KPRB.
REDUCED CIGS AND VSBY WILL MOSTLY CLEAR BY 17Z THOUGH MAY LINGER IN
SOME LOCATIONS UNTIL 20Z. OTHERWISE AND ELSEWHERE VFR CONDITIONS WILL
PREVAIL.

KLAX... LOW TO MODERATE CONFIDENCE IN THE 06Z TAF.  THE REDUCED
CONFIDENCE IS DUE TO THE UNCERTAINTY REGARDS THE INTENSITY AND TIMING
OF THE MARINE INVERSION.  ANY REDUCED CIG AND VSBY WILL MOSTLY CLEAR BY
17Z THOUGH MAY LINGER UNTIL 20Z. OTHERWISE VFR CONDITIONS WILL PREVAIL.

KBUR... MODERATE CONFIDENCE IN THE 06Z TAF.  VFR CONDITIONS ARE
EXPECTED THROUGHOUT THE FORECAST PERIOD HOWEVER THERE IS A 20 PERCENT
CHANCE OF MVFR VSBYS 12Z-17Z.

&&

.MARINE...28/800 PM

SMALL CRAFT ADVISORY CONDITIONS WILL PERSIST FROM POINT PIEDRAS
BLANCAS TO POINT SAL 10-60 NM AND FROM POINT SAL TO SAN CLEMENTE
ISLAND THROUGH SUNDAY. THE STRONGEST NORTHWEST WINDS WILL LIKELY
OCCUR TONIGHT THROUGH EARLY SUNDAY MORNING WITH LOCAL GUSTS TO 35
KT. THERE IS A CHANCE NORTHWEST WINDS WILL INCREASE TO GALE FORCE
NEXT WEEK TUESDAY FROM POINT PIEDRAS TO SAN NICOLAS ISLAND INCLUDING
THE WEST HALF OF SANTA BARBARA CHANNEL AND GALES MAY PREVAIL THROUGH
THURSDAY NIGHT.

A MIXED SWELL IS LIKELY THROUGH THE WEEKEND...WEST-NORTHWEST AT 14
SECONDS...SOUTH SWELL AT 19 SECONDS AND LOCALLY GENERATED NORTHWEST
SWELL AT 8 SECONDS. THE COMBINED SEAS FROM POINT PIEDRAS BLANCAS TO
SAN CLEMENTE ISLAND WILL PEAK 10 TO 12 FEET TONIGHT. THE SHORTER
PERIOD SEAS WILL SUBSIDE SUNDAY THROUGH MONDAY MORNING AND IS
EXPECTED TO REBUILD TUESDAY WHILE A FRESH WEST-NORTHWEST SWELL MIXES
INTO THE COASTAL WATERS TUESDAY. PATCHY DENSE FOG...WITH VSBYS BELOW
1 NM WILL AFFECT AREAS THROUGH THE REMAINDER OF THE MORNING AND
AGAIN SUN MORNING.

&&

.BEACHES...A LONG PERIOD SWELL FROM THE SOUTHERN HEMISPHERE WILL
CONTINUE THROUGH THE REMAINDER OF THE WEEKEND. EXPECT ELEVATED SURF
AND STRONG RIP CURRENTS AND LONGSHORE CURRENTS ON BEACHES ALONG
EXPOSED SOUTH FACING SHORES.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
BEACH HAZARDS STATEMENT (SEE LAXCFWLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&
$$

PUBLIC...SIRARD/HALL
AVIATION...KJ
MARINE...30/SIRARD
SYNOPSIS...SUKUP

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