151
FXUS66 KLOX 181053
AFDLOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
353 AM PDT SUN MAY 18 2025
SYNOPSIS
17/718 PM.
A DEEP MARINE LAYER WILL MAINTAIN BRING EXTENSIVE LOW CLOUDS AND
FOG TO THE AREA OVERNIGHT, BUT BUILDING HIGH PRESSURE WILL BRING
A FEW DEGREES OF WARMING AWAY FROM THE COAST ON SUNDAY. GUSTY
SOUTHWEST WINDS ARE EXPECTED 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.
VERY HOT WEATHER WILL RETURN NEXT WEEK.
SHORT TERM (TDY-TUE)
18/319 AM.
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. LOW CLOUDS WILL
CLEAR BY MID OR LATE MORNING BUT THE LINGERING DEEP MOISTURE MAY
COOK UP INTO A STRATACU DECK THIS AFTERNOON (ESP OVER THE LA
CST/VLYS). THE NW FLOW HAS ALSO CREATED UPSLOPE CLOUDS ACROSS THE
NRN MTNS NEXT TO THE KERN COUNTY LINE. THE NW FLOW AND MODERATE
ONSHORE FLOW TO THE EAST HAVE BROUGHT ADVISORY LEVEL GUSTS TO THE
ANTELOPE VLY AND ITS WESTERN FOOTHILLS AS WELL AS THE I-5
COORIDOR. LATER THIS AFTERNOON ADVISORY LEVEL WINDS WILL DEVELOP
AGAIN ACROSS MUCH OF THE SBA SOUTH COAST. RISING HGTS IN THE WAKE
OF YDY'S TROF WILL COMBINE WITH WEAKER ONSHORE FLOW AND, MOST
IMPORTANTLY, MUCH MORE SUNSHINE TO BRING 3 TO 6 DEGREES OF
WARMING TO THE COASTS AND 6 TO 12 DEGREES OVER THE REST OF THE
AREA. THIS WARMING WILL NOT BE ENOUGH, HOWEVER, TO BRING MAX TEMPS
UP TO NORMALS.
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
18/1052Z.
AROUND 07Z, THE MARINE LAYER DEPTH WAS NEAR 2200 FEET DEEP AT KLAX.
THE TOP OF THE MARINE INVERSION WAS NEAR 2500 FEET WITH A
TEMPERATURE NEAR 12 DEGREES CELSIUS. THERE WAS ANOTHER INVERSION
ABOVE UP TO AROUND 4700 FEET.
LOW TO MODERATE CONFIDENCE IN THE CURRENT FORECAST FOR ALL
TERMINALS, EXCEPT HIGH CONFIDENCE IN THE CURRENT FORECAST FOR
DESERT TERMINALS. CONDITIONS COULD VARY BETWEEN MVFR AND VFR
THROUGH THIS MORNING. THERE IS A MODERATE CHANCE OF IFR
CONDITIONS THROUGH 14Z. OTHERWISE, MVFR CONDITIONS WILL LIKELY
PERSIST THROUGH AT LEAST 15Z AT CENTRAL COAST TERMINALS AND LOS
ANGELES COUNTY COASTAL AND VALLEYS TERMINALS, THEN VFR CONDITIONS
SHOULD DEVELOP THROUGH 19Z. THERE IS A MODERATE TO HIGH CHANCE OF
LIFR TO IFR CONDITIONS AFTER 08Z MONDAY FOR CENTRAL COAST
TERMINALS AND LOS ANGELES COUNTY COASTAL TERMINALS.
KLAX...MVFR CONDITIONS WILL LIKELY PERSIST THROUGH AT
LEAST 16Z, THEN VFR CONDITIONS COULD DEVELOP AS SOON AS 16Z, OR AS
LATE AS 19Z. THERE IS A 50 PERCENT CHANCE OF IFR CONDITIONS AFTER
08Z MONDAY. ANY EAST WINDS SHOULD REMAIN LESS THAN 7 KNOTS.
KBUR...MVFR CONDITIONS WILL LIKELY PERSIST THROUGH AT
LEAST 15Z, THEN VFR CONDITIONS COULD DEVELOP AS SOON AS 15Z, OR
AS LATE AS 17Z.
MARINE
18/352 AM.
LOWER CONFIDENCE EXISTS IN THE CURRENT FORECAST. HIGHER CONFIDENCE
IN THE CURRENT FORECAST FOR SEAS. LOWER CONFIDENCE IN THE CURRENT
FORECAST FOR WINDS.
FOR THE WATERS SOUTHWEST THROUGH NORTHWEST OF THE CHANNEL ISLANDS
AND THE NEARSHORE WATERS ALONG THE CENTRAL COAST, THERE IS A
80-100 PERCENT OF SMALL CRAFT ADVISORY (SCA) CONDITIONS THROUGH
LATE MONDAY NIGHT OR EARLY TUESDAY. THERE IS A 30-50 PERCENT
CHANCE OF GALES THIS MORNING, INCREASING TO A 50-80 PERCENT CHANCE
THIS AFTERNOON AND EVENING. THE HIGHEST CHANCES WILL BE FOR THE
WATERS FROM POINT CONCEPTION SOUTH TO SAN NICOLAS ISLAND, 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 30-60 PERCENT CHANCE, BUT THE CHANCE WILL INCREASE
AGAIN TO A 40-70 PERCENT CHANCE BY MONDAY AFTERNOON AND EVENING.
INSIDE THE SOUTHERN CALIFORNIA BIGHT, THERE IS A 30-50 PERCENT
CHANCE OF SCA LEVEL WINDS THROUGH THIS AFTERNOON, THEN THE CHANCES
WILL INCREASE TO 40-70 PERCENT. THE HIGHEST CHANCES WILL BE FOR
THE WESTERN SANTA BARBARA CHANNEL, WHILE THE LOWEST CHANCE WILL BE
FOR SANTA MONICA BAY. THERE IS A LESSER CHANCE OF SCA LEVEL WINDS
THEREAFTER, WITH HIGH CONFIDENCE ON WINDS DROPPING BELOW SCA
LEVELS UNTIL AT LEAST THURSDAY.
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).
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
AVIATION...HALL
MARINE...HALL
SYNOPSIS...MW/CILIBERTI
WEATHER.GOV/LOSANGELES
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX
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