666
FXUS66 KLOX 181743
AFDLOX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1043 AM PDT SUN MAY 18 2025
UPDATED AVIATION SECTION
SYNOPSIS
18/908 AM.
SLIGHTLY WARMER TEMPERATURES ARE ON TAP FOR TODAY, THEN VERY HOT
WEATHER AND CLEAR SKIES IS EXPECTED STARTING MONDAY THROUGH THE
WORKWEEK. HIGH TEMPERATURES WILL BE WELL ABOVE NORMAL FOR THIS
TIME OF YEAR EACH WEEK DAY. GUSTY SOUTHWEST WINDS ARE EXPECTED
THROUGH TONIGHT IN THE ANTELOPE VALLEY, WHILE GUSTY NORTH WINDS
ARE EXPECTED ACROSS SOUTHWEST SANTA BARBARA COUNTY AND IN THE LOS
ANGELES COUNTY MOUNTAINS NEAR THE GRAPEVINE.
SHORT TERM (TDY-TUE)
18/910 AM.
***UPDATE***
MARINE LAYER CLOUDS ARE IN THE PROCESS OF BURNING OFF THIS
MORNING, HOWEVER LINGERING DEEP MOISTURE MAY COOK UP INTO A
STRATOCUMULUS DECK THIS AFTERNOON (ESPECIALLY OVER THE LA
COASTS/VALLEYS). THE WEAKENING ONSHORE FLOW COMBINED WITH RISING
500 MB HEIGHTS AND MUCH MORE SUNSHINE (COMPARED TO THE LAST
SEVERAL DAYS) WILL ALLOW FOR 3 TO 6 DEGREES OF WARMING AT THE
COASTS AND 6 TO 12 DEGREES OVER THE REST OF THE AREA. HIGH TEMPERATURES
WILL LARGELY BE IN THE 70S TODAY, WITH SOME OF THE WARMER VALLEYS
SQUEAKING INTO THE 80S, AND THE COASTS IN THE 60S TO LOW 70S.
THIS WARMING WILL NOT BE ENOUGH, HOWEVER, TO BRING MAX TEMPS UP TO
NORMALS.
THE NW FLOW AND MODERATE ONSHORE FLOW TO THE EAST HAVE BROUGHT
ADVISORY LEVEL GUSTS TO THE ANTELOPE VALLEY AND ITS WESTERN
FOOTHILLS AS WELL AS THE I-5 CORRIDOR. LATER THIS AFTERNOON,
ADVISORY LEVEL WINDS WILL DEVELOP AGAIN ACROSS MUCH OF THE SBA
SOUTH COAST.
NO UPDATES WERE NEEDED TO THE MORNING FORECAST. WILL BE LOOKING AT
POTENTIALLY ADDING SOME WIND ADVISORIES FOR THE SANTA BARBARA
MOUNTAINS AND SOUTH COAST, AND POSSIBLY THE VENTURA COUNTY
MOUNTAINS FOR LATER THIS AFTERNOON AND EVENING. ADDITIONALLY, WILL
BE ASSESSING THE NEED FOR HEADLINES FOR THE MULTI-DAY HEAT EVENT
THIS WEEK.
***FROM PREVIOUS DISCUSSION***
THE MARINE LAYER IS ABOUT 4500 FT DEEP AND CONTAINS TWO
INVERSIONS. THIS HAS GENERATED TWO SEPARATE CLOUD LAYERS. IN
ADDITION OFFSHORE TRENDS AND INCREASING NW FLOW ALOFT HAVE
DISRUPTED THE LOW CLOUD FORMATION IN MANY PLACES. THE NW FLOW HAS
ALSO CREATED UPSLOPE CLOUDS ACROSS THE NRN MTNS NEXT TO THE KERN
COUNTY LINE.
CONTINUED OFFSHORE TRENDS WILL LEAD TO ACTUAL OFFSHORE FLOW MONDAY
MORNING, ESP FROM THE NORTH. MARINE LAYER STRATUS WILL LIKELY BE
CONFINED TO THE LA COUNTY BEACHES AND THERE IS A 30 PERCENT CHC
THAT EVEN THESE AREAS WILL BE CLOUD FREE. RIDGING WILL MOVE OVER
THE STATE AND HGTS WILL RISE TO 582 DAM. MAX TEMPS WILL JUMP 3 TO
6 DEGREES ACROSS THE COASTS AND 6 TO 12 LOCALLY 15 DEGREES OVER
THE REST OF THE AREA. MOST MAX TEMPS WILL END UP 4 TO 8 DEGREES
ABOVE NORMAL.
THE RIDGE FLATTENS OUT ON TUESDAY BUT HGTS RISE A COUPLE OF DAM UP
TO 584 DAM. THE OFFSHORE FLOW CONTINUES AND SKIES WILL BE CLOUD
FREE. MOST OF SLO AND SBA COUNTIES WILL ONLY WARM 1 OR 2 DEGREES.
VTA AND LA COUNTIES, HOWEVER, WILL SEE ANOTHER 4 TO 8 DEGREES OF
WARMING AS THE OFFSHORE FLOW WILL HAVE THE GREATEST AFFECT IN THIS
LOCATION. LOOK FOR 4 TO 8 DEGREES OF ADDITIONAL WARMING. MAX TEMPS
ACROSS THE CSTS WILL BE IN THE 70S EXCEPT THE INTERIOR PORTIONS
OF THE LA/VTA CSTS WHERE LOWER TO MID 80S WILL BE COMMON. THE VLYS
WILL ALL SEE MAX TEMPS IN THE 90S. THESE TEMPS WILL BE CLOSE TO
ADVISORY CRITERIA BUT JUST UNDER. STILL PEOPLE WORKING OR PLAYING
OUTSIDE IN THE VLYS SHOULD BE AWARE OF HEAT DANGERS.
LONG TERM (WED-SAT)
18/332 AM.
HGTS AND TEMPS PEAK ON WEDNESDAY AND IT LOOKS LIKE THE VLYS WILL
SEE MAX TEMPS FROM 95 TO 103 DEGREES (15 TO 20 DEGREES ABOVE
NORMAL). IN ADDITION THERE WILL BE A VERY STRONG INVERSION AROUND
1000 FT (RIGHT AT MANY VLY ELEVATIONS) AND THIS WILL ALSO KEEP
MANY OVERNIGHT LOWS WILL ABOVE NORMAL. SLIGHTLY LOWER HGTS AND
SLIGHTLY STRONGER ONSHORE FLOW WILL BRING SOME COOLING THURSDAY
BUT NOT REALLY ENOUGH TO REDUCE THE HEAT DANGER. HEAT ADVISORIES
LOOK VERY LIKELY FOR BOTH DAYS AND PEOPLE SHOULD TAKE NOTICE AND
PERHAPS ADJUST ANY OUTDOOR PLANS. THERE WILL STILL BE SOME ONSHORE
FLOW TO THE EAST AND THIS WILL MAKE THE BEACH TEMPERATURE
FORECAST TRICKY AS THERE COULD BE A HUGE TEMP GRADIENT BETWEEN THE
BEACHES AND THE INLAND AREAS.
THE RIDGE WEAKENS AND ONSHORE FLOW INCREASES BOTH ON FRI AND SAT.
A SHALLOW MARINE LAYER CLOUD DECK COULD DEVELOP ACROSS SOME OF THE
COASTS. MAX TEMPS WILL FALL 3 TO 6 DEGREES FRI AND THEN 5 TO 10
DEGREES ON SAT. BY SAT MOST MAX TEMPS WILL ONLY BE 3 OR SO DEGREES
OVER NORMAL.
AVIATION
18/1742Z.
AT 1704Z, THE MARINE LAYER DEPTH WAS NEAR 3000 FEET DEEP AT KLAX.
THE TOP OF THE WEAK MARINE INVERSION WAS NEAR 4800 FEET WITH A
TEMPERATURE NEAR 10 DEGREES CELSIUS.
MODERATE CONFIDENCE IN TAFS FOR KLAX, KSMO, AND KLGB. SCT TO BKN
CIGS 020-030 WILL CONTINUE THROUGH EARLY THIS AFTERNOON,
OCCASIONALLY BOUNCING FLIGHT CATS BETWEEN VFR AND MVFR.
HIGH CONFIDENCE IN REMAINING TAFS. AT KPMD AND KWJF, LIGHT LLWS
AND LIGHT TO MODERATE TURBULENCE MAY IMPACT THE TERMINAL THROUGH
10Z. THERE IS A CHANCE CIGS DO NOT REACH KLAX (50%) OR KLGB (30%)
TONIGHT, AND 30% CHANCE THEY DO REACH KSMO.
KLAX...MODERATE CONFIDENCE IN TAF. CIGS 020-030 MAY BOUNCE BETWEEN
SCT AND BKN THROUGH 21Z. THERE IS A 50% CHANCE CIGS DO NOT REACH
THE TERMINAL TONIGHT. IF THEY DO ARRIVE, THERE IS A 30% CHANCE
OF CIGS 007-009. NO SIGNIFICANT EAST WIND COMPONENT EXPECTED.
KBUR...HIGH CONFIDENCE IN TAF. CIGS 020-030 MAY BOUNCE BETWEEN
SCT AND BKN THROUGH 21Z. OTHERWISE, VFR CONDS EXPECTED THROUGH THE
PERIOD.
MARINE
18/909 AM.
RELATIVELY LOW CONFIDENCE IN THE CURRENT FORECAST. HIGHER
CONFIDENCE IN THE CURRENT FORECAST FOR SEAS COMPARED TO WINDS.
FOR THE OUTER WATERS AND THE NEARSHORE WATERS ALONG THE CENTRAL
COAST, THERE IS A 80-100 PERCENT OF SMALL CRAFT ADVISORY (SCA)
CONDITIONS THROUGH TUESDAY NIGHT, EXCEPT FOR LULLS NEARSHORE ALONG
THE CENTRAL COAST IN THE OVERNIGHT/EARLY MORNING HOURS. WHILE
LOCAL GALE FORCE WIND GUSTS MAY OCCUR THIS MORNING, CHANCES FOR
MORE WIDESPREAD GALES INCREASE TO 50-80 PERCENT CHANCE THIS
AFTERNOON INTO THE LATE NIGHT HOURS. THE HIGHEST CHANCES WILL BE
FOR THE MAJORITY OF THE OUTER WATERS, WHILE THE LOWEST CHANCES
WILL BE FOR THE NEARSHORE WATERS ALONG THE CENTRAL COAST. THE
CHANCES FOR GALES WILL REDUCE EARLY MONDAY MORNING TO A 40-60
PERCENT CHANCE, BUT THE CHANCES WILL INCREASE AGAIN TO A 50-80
PERCENT CHANCE BY MONDAY AFTERNOON INTO THE LATE NIGHT HOURS,
WITH HIGHEST CHANCES FOR THE NORTHERN OUTER WATERS. THEN, THERE IS
A 30-40 PERCENT CHANCE FOR GALES AGAIN TUESDAY AFTERNOON THROUGH
LATE NIGHT.
INSIDE THE SOUTHERN CALIFORNIA BIGHT, THERE IS A 60 PERCENT
CHANCE OF SCA LEVEL WINDS THIS AFTERNOON THROUGH LATE TONIGHT,
FOCUSED ACROSS THE WESTERN PORTION OF THE SANTA BARBARA CHANNEL.
LOCAL GALE FORCE WIND GUSTS MAY OCCUR IN THE VERY EXTREME WESTERN
PORTION OF THE CHANNEL. WINDS ARE EXPECTED TO REMAIN BELOW SCA
LEVELS IN THE SOUTHERN INNER WATERS EXCEPT FOR LOCAL GUSTS TO
20-25 KTS IN TYPICAL WINDY SPOTS, INCLUDING THE SAN PEDRO CHANNEL.
SLIGHTLY HIGHER CHANCES EXIST FOR SCA LEVEL WINDS MONDAY
AFTERNOON INTO THE EVENING HOURS, BUT STRONGEST WINDS WILL MOST
LIKELY REMAIN AWAY FROM THE IMMEDIATE COAST. LOWER CHANCES EXIST
TUESDAY.
LOX WATCHES/WARNINGS/ADVISORIES
CA...WIND ADVISORY REMAINS IN EFFECT UNTIL 10 AM PDT MONDAY FOR
ZONE 378. (SEE LAXNPWLOX).
WIND ADVISORY REMAINS IN EFFECT UNTIL 3 AM PDT MONDAY FOR
ZONES 381-383. (SEE LAXNPWLOX).
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 PM PDT THIS AFTERNOON
FOR ZONES 645-670-673-676. (SEE LAXMWWLOX).
GALE WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 9 PM PDT
THIS EVENING FOR ZONE 645. (SEE LAXMWWLOX).
GALE WATCH IN EFFECT FROM MONDAY AFTERNOON THROUGH MONDAY
EVENING FOR ZONE 645. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3
AM PDT MONDAY FOR ZONE 650. (SEE LAXMWWLOX).
GALE WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 3 AM PDT
TUESDAY FOR ZONE 670. (SEE LAXMWWLOX).
GALE WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 3 AM PDT
MONDAY FOR ZONES 673-676. (SEE LAXMWWLOX).
GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH LATE MONDAY
NIGHT FOR ZONES 673-676. (SEE LAXMWWLOX).
PUBLIC...RORKE/LUND
AVIATION...LEWIS
MARINE...HALL/LEWIS
SYNOPSIS...KL
WEATHER.GOV/LOSANGELES
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page