Weather Service Report


808 
FXUS66 KLOX 272058 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
200 PM PDT FRI MAR 27 2015

.SYNOPSIS...
HIGH PRESSURE ALOFT WILL CONTINUE TO MOVE FURTHER EAST OF THE AREA 
TO ALLOW FOR COOLER CONDITIONS THIS WEEKEND...ALONG WITH OVERNIGHT 
LOW CLOUDS AND FOG IN SOME COASTAL AREAS...SOME FOG POSSIBLY LOCALLY 
DENSE. HIGH PRESSURE WILL RETURN ON MONDAY FOR WARMER CONDITIONS.   
HIGH TEMPERATURES WILL VARY SOME DAILY BUT REMAIN ABOVE NORMAL 
THROUGH NEXT WEEK.

&&

.SHORT TERM (SAT-MON)...
THE UPPER LEVEL TROUGH TO BRING COOLER ONSHORE FLOW CONDITIONS TO 
THE FORECAST AREA IS JUST OFF THE WEST COAST THIS AFTERNOON. 
TEMPERATURES ARE FOR SURE COOLER ALONG THE COAST...ESPECIALLY THE 
CENTRAL COAST WHERE ONSHORE FLOW IS GREATEST AND STRATUS HUGS MUCH 
OF THE COAST. SOUTH OF POINT CONCEPTION REMAINS CLEAR AND THE SEA 
BREEZE SHOULD MARCH ITS WAY INLAND TO KEEP HIGHS IN CHECK. DOWNTOWN 
LOS ANGELES TIED THEIR RECORD OF 91 JUST A BIT GO AND THERE MAY BE 
ENOUGH TIME TO GET ANOTHER DEGREE OR SO BEFORE THE SEA BREEZE MOVES 
THROUGH. BURBANK HAS AT LEAST TIED...AND PASO ROBLES AND SANDBERG 
BOTH BROKE THEIR RECORDS. RER'S TO BE ISSUED SHORTLY.

STRATUS SHOULD STICK AROUND THE CENTRAL COAST TONIGHT AND 
MOVE INLAND...WHILE STRATUS OVER COASTAL L.A. AND VTU COUNTY IS A 
LITTLE MORE UNCERTAIN. FORECAST PUTS IT INTO LGB AND LAX BUT NOT 
EXPECTING IT TO GO MUCH FURTHER. CONTINUED COOLING TOMORROW...BUT 
STILL PLENTY ABOVE NORMAL...THEN ANOTHER CHANCE OF COASTAL OVERNIGHT 
STRATUS SATURDAY NIGHT OVER L.A. AND VTU COUNTY. STRATUS SHOULD STAY 
AWAY FROM THE CENTRAL COAST SATURDAY NIGHT DUE TO ENOUGH OF AN 
OFFSHORE GRADIENT. TEMPS COOL FURTHER ON SUNDAY WITH THE WEAK TROUGH 
MOVING BY EARLY. THE TROUGH MAY ALSO BRING AN INCREASE IN HIGH 
CLOUDS ON SUNDAY.

ANOTHER RIDGE MOVES IN ON MONDAY FOR ANOTHER WARM UP BUT NOT AS 
DRAMATIC AS WHAT WE'VE EXPERIENCED THE PAST COUPLE OF DAYS. HIGHS 
PLENTY ABOVE NORMAL BUT RELATIVELY TAME.

.LONG TERM (TUE-FRI)...
MODELS STILL SHOWING FAIRLY FLAT WESTERLY ZONAL FLOW FOR THIS 
PERIOD. GFS AND EC SHOW A WEAK TROUGH SLIDING THROUGH TO OUR NORTH 
WHICH COULD BRING SOME WINDS TO SOME MOUNTAIN AREAS...BUT OTHERWISE 
TEMPS REMAINING ABOVE NORMAL THROUGHOUT. COULD SEE A SLIGHT BUMP UP 
IN TEMPERATURES ON FRIDAY SINCE THE MODELS ARE FORECASTING A WEAK 
RIDGE BY THEN. AN EDDY CIRCULATION WILL BRING CHANCES OF OVERNIGHT 
STRATUS TO COASTAL L.A. COUNTY EACH NIGHT AND EARLY MORNING. 

&&

.AVIATION...27/1800Z.

MID/UPPER LEVEL TROUGH OF LOW PRESSURE OVER THE EASTERN PACIFIC WILL 
APPROACH WHILE A RIDGE OF HIGH PRESSURE OVER THE AREA SHIFTS EAST. 
UPPER LEVEL LIGHT SOUTHWEST WINDS WILL BECOME MODERATE SOUTHWEST 
AFTER 28/13Z WHILE MID LEVEL LIGHT SOUTH-SOUTHWEST WINDS PREVAIL 
OVER THE AREA. MARINE INVERSION WAS NEAR THE SURFACE OVER THE LA 
BASIN AND NEAR .5FT ALONG THE CENTRAL COAST. THE LOW LEVEL CLOUD 
FIELD WAS OVERCAST WEST AND NORTH OF THE CHANNEL ISLANDS. THE 
INVERSION WILL DIFFER BY PLUS .8KFT SATURDAY MORNING AND 
BROKEN OVER THE BIGHT. WEAK TO MODERATE ONSHORE PRESSURE 
GRADIENT THROUGH 28/04Z AND AFTER 28/19Z OTHERWISE MIXED WEAK 
NORTHERLY AND ONSHORE GRADIENT.
   
MARINE LAYER AT LAX AT 1545Z IS 0 FEET DEEP AND THE INVERSION TOP IS 
AT 2601 FEET WITH A TEMP OF 24 DEGREES C.

KLAX...THERE IS A CHANCE VSBY 4SM BR BETWEEN 28/08-28/11Z AND A 
CHANCE CIGS 003 AND VSBY 1SM BR BETWEEN 28/11-28/16Z THEN 5-6SM HZ 
BETWEEN 28/16-28/20Z. 

KBUR...THERE IS A CHANCE CURRENT SKY/VSBY CONDITIONS WILL PERSIST 
THROUGH 28/13Z AND A CHANCE VSBY 6SM HZ AFTER 28/13Z.

VIRTUALLY CERTAIN - 95-100%
VERY LIKELY       - 80-95%
LIKELY            - 60-80%
CHANCE            - 30-60%
VERY UNLIKELY     - 20% OR LESS

&&

.MARINE...27/200 PM

THERE IS A CHANCE SMALL CRAFT ADVISORY CONDITIONS WILL EXIST FROM 
POINT PIEDRAS BLANCAS TO POINT SAL 10-60 NM AND FROM POINT SAL TO 
SAN CLEMENTE ISLAND THIS AFTERNOON THROUGH SUNDAY. THE STRONGEST 
NORTHWEST WINDS WILL LIKELY OCCUR SATURDAY AFTERNOON 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. A MIXED SWELL IS LIKELY THROUGH THE WEEKEND...  
WESTNORTHWEST 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 
SATURDAY NIGHT. THE SHORTER PERIOD SEAS WILL SUBSIDE SUNDAY THROUGH 
MONDAY MORNING AND IS EXPECTED TO REBUILD TUESDAY WHILE A FRESH 
WESTNORTHWEST SWELL MIXES INTO THE COASTAL WATERS TUESDAY. PATCHY 
DENSE FOG...WITH VSBYS BELOW 1 NM WILL AFFECT MUCH OF THE COASTAL 
WATERS THROUGH SAT MORNING.

&&

.BEACHES...A LONG PERIOD SWELL FROM THEN SOUTHERN HEMISPHERE WILL 
CONTINUE THROUGH 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).

&&

$$

PUBLIC...JACKSON
AVIATION/MARINE...30
SYNOPSIS...SETO

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