512  
FXUS66 KLOX 220530  
AFDLOX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
1030 PM PDT FRI MAR 21 2025  
   
SYNOPSIS
 
21/800 PM.  
 
DRY AND OCCASIONALLY BREEZY CONDITIONS ARE EXPECTED THROUGH NEXT  
WEEK. TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL TODAY  
AND SATURDAY, THEN A SIGNIFICANT WARMUP IS EXPECTED SUNDAY INTO  
MONDAY. HIGH TEMPERATURES ON MONDAY WILL BE WELL ABOVE NORMAL,  
WITH TEMPERATURES IN THE 90S ACROSS THE WARMEST VALLEYS OF LOS  
ANGELES AND VENTURA COUNTIES. A COOLING TREND WILL COMMENCE AFTER  
TUESDAY WITH TEMPERATURES CLOSER TO NORMAL FOR THE REMAINDER OF  
NEXT WEEK.  
 

 
   
SHORT TERM (FRI-MON)
 
21/846 PM.  
 
***UPDATE***  
 
TODAY WAS ANOTHER WARM DAY, WITH TEMPERATURES IN THE MID 70S TO  
LOW 80S ACROSS THE WARMEST VALLEYS OF VENTURA AND LOS ANGELES  
COUNTIES, WITH THE REMAINDER OF THE AREA IN 60S TO MID 70S. A  
WEAK TROUGH OVER THE NORTHERN HALF OF THE WEST COAST HAS ALLOWED  
SOME HIGHER LEVEL CLOUDS TO MOVE INTO THE CENTRAL COAST COUNTIES  
THIS EVENING, RESULTING IN PARTLY CLOUDY SKIES. NORTH WIND GUSTS  
OF 30-50 MPH HAVE BEEN REPORTED ACROSS THE SOUTHERN PORTION OF  
SANTA BARBARA COUNTY, THUS HAVE ISSUED A SHORT WIND ADVISORY UNTIL  
6AM SATURDAY, THOUGH WOULD NOT BE SURPRISED IF THE WINDS DROP OFF  
BY 3AM AND THE ADVISORY IS CANCELLED EARLY.  
 
AS OFFSHORE FLOW FROM THE EAST HAS WEAKENED WITH THE LAX-DAG  
GRADIENT AROUND 0, THE LOS ANGELES COUNTY COAST COULD SEE A  
RETURN OF MARINE LAYER CLOUDS TONIGHT, ESPECIALLY CONSIDERING A  
THIN LAYER OF LOW LEVEL CLOUDS FORMED EARLY THIS MORNING. HOWEVER,  
CURRENT SATELLITE IMAGERY SHOWS ONLY HIGHER LEVEL CLOUDS TO THE  
NORTH AND NO MARINE LAYER CLOUDS IN SIGHT, MEANING THE LOW LEVEL  
CLOUD DECK COULD HOLD OFF ON FORMING. IF LOW CLOUDS DO FORM, IT  
WOULD OCCUR VERY LATE TONIGHT INTO EARLY SATURDAY MORNING.  
 
A WEAK INSIDE SLIDER WILL PASS BY THE AREA STARTING SATURDAY  
AFTERNOON AS A RIDGE BUILDS IN BEHIND IT. SOME MORE HIGHER LEVEL  
CLOUDS WILL BE PULLED OVER THE REGION FROM THE NORTH AS THIS  
INSIDE SLIDER FORMS, MAKING FOR ONCE AGAIN A PARTLY CLOUDY DAY ON  
SATURDAY. THESE CLOUDS COMBINED WITH SLIGHTLY LOWERING 500 MB  
HEIGHTS OF A FEW DECAMETERS (DAM) WILL CAUSE MOST OF THE AREA TO  
SEE A FEW DEGREES OF COOLING. OFFSHORE FLOW WILL INCREASE AGAIN AS  
THE RIDGE BUILDS IN, BRINGING SLIGHTLY STRONGER (COMPARED TO  
TODAY), BUT STILL WEAK NORTH TO NORTHEAST WINDS LATE SATURDAY  
EVENING INTO EARLY SUNDAY MORNING. THESE WINDS WILL LIKELY BE  
SUB- ADVISORY, GENERALLY 25-40 MPH, AND LIKELY STAY CONFINED TO  
THE INTERIOR MOUNTAINS (INCLUDING THE I-5 CORRIDOR), SANTA LUCIA  
MOUNTAINS, AND ENTIRE SOUTHERN SANTA BARBARA COUNTY. HOWEVER, SOME  
LOCAL 45-50 MPH GUSTS WILL BE POSSIBLE AND ADVISORIES CAN'T BE  
COMPLETELY RULED OUT - ESPECIALLY FOR SOUTHERN SANTA BARBARA COAST  
NEAR MONTECITO.  
 
ADDED WIND ADVISORIES FOR TONIGHT FOR THE WESTERN SANTA YNEZ  
MOUNTAINS AND THE SOUTHERN SANTA BARBARA COAST, AND SLIGHTLY  
ADJUSTED HIGH TEMPERATURES A LITTLE COOLER ON SATURDAY. OTHERWISE  
FORECAST WAS IN SHAPE AND NO OTHER UPDATES WERE NEEDED.  
 
***FROM PREVIOUS DISCUSSION***  
 
A WEAK UPPER LEVEL TROUGH WILL BRING AN INCREASE IN ONSHORE  
PRESSURE GRADIENTS LATE TONIGHT THROUGH SATURDAY WITH POSSIBLE LOW  
CLOUDS DUE TO A STRENGTHENING MARINE LAYER NEAR THE COAST OF LOS  
ANGELES, ESPECIALLY TOWARDS THE BORDER WITH ORANGE COUNTY, BUT  
OTHER AREAS THE COVERAGE SHOULD BE MINIMAL. SATURDAY AFTERNOON  
SEABREEZES WILL ALSO BE QUITE GUSTY ESPECIALLY THROUGH THE PASSES  
AND CANYONS. TEMPERATURES WILL BE A COUPLE OF DEGREES COOLER ON  
SATURDAY NEAR THE COAST AND VALLEYS BUT OTHERWISE NOT MUCH CHANGE  
THERE EITHER.  
 
AN UPPER LEVEL RIDGE WILL BEGIN TO STRENGTHEN ON SUNDAY BRINGING  
A PRONOUNCED WARMING PERIOD TO THE REGION THAT WILL STRETCH  
THROUGH EARLY NEXT WEEK, WITH SIGNIFICANTLY ABOVE NORMAL  
TEMPERATURES.  
   
LONG TERM (TUE-FRI)
 
21/202 PM.  
 
AN UPPER LEVEL RIDGE WILL BE STRONG EARLY NEXT WEEK OVER SOUTHERN  
CALIFORNIA, PEAKING LIKELY MONDAY WITH A 584 DM RIDGE OVER SE CA  
AND SW AZ. LIGHT NORTH TO NORTHEAST WINDS AWAY FROM THE COAST,  
COMBINED WITH A SHALLOW MARINE LAYER, WILL SUPPORT HIGHS MONDAY  
AROUND 20 DEGREES ABOVE NORMAL IN MOST AREAS. TEMPERATURES  
WILL RISE INTO THE LOWER TO MID 90S OVER THE COASTAL VALLEYS IN  
LOS ANGELES AND VENTURA COUNTIES. HEAT ADVISORIES MAY BE NEEDED  
FOR LOCAL AREAS IN LOS ANGELES BY MONDAY.  
 
HEIGHTS WILL FALL BY WEDNESDAY AS AN UPPER LOW APPROACHES THE  
REGION, WITH FALLING HEIGHTS AND INCREASING ONSHORE FLOW.  
 
ADDITIONAL COOLING IS POSSIBLY ON THURSDAY AS A LARGER TROUGH  
MOVES INTO THE EASTERN PACIFIC, BUT THERE IS A CHANCE THAT COOLING  
FROM THAT SYSTEM WILL NOT OCCUR UNTIL FRI. IN ANY EVENT, MAX  
TEMPS WILL LIKELY STILL BE SEVERAL DEGREES ABOVE NORMAL IN MOST  
AREAS WED AND THU, THOUGH NIGHT THRU MORNING LOW CLOUDS MAY RETURN  
TO COASTAL AREAS.  
 
LONGER TERM ENSEMBLE GUIDANCE SHOWS THE POTENTIAL FOR RAIN BY THE  
FIRST FEW DAYS OF APRIL, STAY TUNED AS WE CONTINUE TO EXAMINE THE  
LATEST FORECAST DATA!  
 

 
   
AVIATION
 
22/0529Z.  
 
AT 0455Z AT KLAX, THE MARINE LAYER WAS AROUND 700 FEET DEEP. THE  
TOP OF THE INVERSION WAS 1700 FEET WITH A TEMPERATURE OF 17 C.  
 
HIGH CONFIDENCE IN TAF PACKAGE. THERE IS A 10% CHC OF LIFR CONDS  
AT KPRB FROM 10Z-18Z SAT. THERE IS A 10-20% CHC OF MVFR/IFR CONDS  
AT KLAX AND KLGB FROM 08Z-17Z SAT.  
 
KLAX...HIGH CONFIDENCE IN TAF. THERE IS A SLIGHT CHANCE (10-20%)  
OF MVFR CIGS (010-015) AND A NON-ZERO CHC OF HIGH-END IFR CONDS  
FROM 12Z-16Z SAT, AND A 20-30% CHC AGAIN AFTER 09Z SUN. NO  
SIGNIFICANT EAST WIND COMPONENT IS EXPECTED.  
 
KBUR...HIGH CONFIDENCE IN TAF.  
 

 
   
MARINE
 
21/536 PM.  
 
FOR THE OUTER WATERS, HIGH CONFIDENCE IN A COMBINATION OF SMALL  
CRAFT ADVISORY (SCA) LEVEL NORTHWEST WINDS AND SEAS CONTINUING  
THROUGH SUNDAY. LOCALIZED GALE FORCE NW GUSTS ARE POSSIBLE TO  
LIKELY FROM THIS AFTERNOON THRU THE LATE NIGHT HOURS TONIGHT IN  
PZZ676/673.  
 
POTENTIAL FOR GALE FORCE WIND GUSTS ARE EXPECTED TO BECOME MORE  
WIDESPREAD TOMORROW - EXPANDING INTO PZZ670. COMPARING YESTERDAY'S  
BUOY OBSERVATIONS TO MODEL GUIDANCE, THE HREF WAS A CLOSE MATCH.  
THE HREF PROBABILITIES FOR GALES HAS TRENDED UPWARDS THE LAST  
FEW CYCLES INCREASING CONFIDENCE. THE SPATIAL COVERAGE OF GALES  
APPEARS TO BE ADEQUATE ALONG WITH OTHER FACTORS, TO WARRANT A  
GALE WARNING FOR PZZ676 TOMORROW AFTERNOON INTO THE LATE NIGHT  
HOURS.  
 
REGARDING PZZ673/670, IT APPEARS SPATIAL COVERAGE WILL BE  
ADEQUATE. HOWEVER, IT IS UNCERTAIN IF GALES WILL BECOME WIDESPREAD  
OR REMAIN LOCAL. THUS, HAVE HELD BACK OFF ON A GALE WARNING AND  
WILL LET THE MID-SHIFT DECIDE. FOR MONDAY AND TUESDAY, HIGH  
CONFIDENCE IN WINDS AND SEAS REMAINING BELOW SCA LEVELS.  
 
FOR THE INNER WATERS NORTH OF POINT SAL, HIGH CONFIDENCE IN  
CURRENT FORECAST. THERE IS A 80-90% CHANCE OF SCA LEVEL NW WINDS  
SATURDAY DURING THE AFTERNOON AND EVENING HOURS. ON SUNDAY, THERE  
IS A 30-40% CHANCE OF SCA LEVEL WINDS IN THE AFTERNOON AND EVENING  
HOURS. FOR MONDAY AND TUESDAY, HIGH CONFIDENCE IN WINDS AND SEAS  
REMAINING BELOW SCA LEVELS.  
 
FOR THE INNER WATERS SOUTH OF POINT CONCEPTION, MODERATE  
CONFIDENCE IN CURRENT FORECAST. THERE IS A 70% CHANCE OF SCA  
LEVEL NW WINDS FOR THE WESTERN PORTION OF THE SANTA BARBARA  
CHANNEL DURING THE AFTERNOON TO LATE EVENING HOURS ON SATURDAY.  
SCA WINDS COULD LINGER FOR A FEW HOURS AFTER MIDNIGHT. OTHERWISE,  
WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA LEVELS THROUGH  
TUESDAY.  
 

 
   
LOX WATCHES/WARNINGS/ADVISORIES
 
 
CA...WIND ADVISORY IN EFFECT UNTIL 6 AM PDT SATURDAY FOR ZONES  
349-351. (SEE LAXNPWLOX).  
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 PM PDT SUNDAY FOR  
ZONES 670-673. (SEE LAXMWWLOX).  
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 PM PDT SATURDAY FOR  
ZONE 676. (SEE LAXMWWLOX).  
GALE WARNING IN EFFECT FROM 3 PM SATURDAY TO 3 AM PDT SUNDAY  
FOR ZONE 676. (SEE LAXMWWLOX).  
 

 
 

 
 
PUBLIC...JMB/LUND  
AVIATION...BLACK/LUND  
MARINE...BLACK  
SYNOPSIS...JMB/KL  
 
WEATHER.GOV/LOSANGELES  
 
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:  
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX  
 
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