355
FXUS66 KLOX 290231
AFDLOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
731 PM PDT MON JUL 28 2025
SYNOPSIS
28/131 PM.
ONSHORE FLOW WILL CONTINUE THROUGH THE WEEK AS AN UPPER-LEVEL
TROUGH OF LOW PRESSURE REMAINS ANCHORED ALONG THE WEST COAST. NIGHT
THROUGH MORNING LOW CLOUDS AND FOG WILL REMAIN IN THE FORECAST
FOR MOST COASTAL AND VALLEY LOCATIONS, BUT THE MARINE LAYER WILL
THIN SOME THROUGH MIDWEEK AS HIGH PRESSURE ALOFT THE SOUTHEASTERN
UNITED STATES BUILDS WEST. A SLOW WARMING TREND WILL TAKE SHAPE,
MOST PRONOUNCED AWAY FROM THE COAST.
SHORT TERM (MON-THU)
28/147 PM.
ANOTHER VERY LOW IMPACT WEATHER DAY ACROSS SOUTHWEST CALIFORNIA AS
AN UPPER LEVEL TROUGH REMAINS IN PLACE ALONG THE WEST COAST,
ANCHORED BY AN UNUSUALLY COLD AND MOSTLY STATIONARY LOW PRESSURE
SYSTEM ALONG THE BC COAST. WHILE THE UPPER PATTERN WON'T CHANGE
TOO MUCH THIS WEEK, MODELS HAVE BEEN CONSISTENT SHOWING A SLOW
WARMING TREND THROUGH MID WEEK DUE TO MINOR HEIGHT RISES LOCALLY
AS WELL AS A SLIGHT WEAKENING OF ONSHORE FLOW. FORECAST SOUNDINGS
AGAIN SHOW ADDITIONAL LOWERING OF THE MARINE LYR TONIGHT WHICH
MAKES SENSE WITH THE WARMING ALOFT, THOUGH LIKE THE LAST COUPLE
DAYS THE AMOUNT OF LOWERING PROJECTED IN THE MODELS WILL LIKELY BE
LESS THAN EXPECTED. IN ANY CASE, CONFIDENCE IS HIGH IN THE WARMING
TREND THROUGH WEDNESDAY WITH TEMPERATURES CLIMBING 2-4 DEGREES
EACH DAY, HIGHEST INLAND AND LEAST AT THE COAST. THEN LITTLE
CHANGE THURSDAY.
OVERALL, NO SIGNIFICANT ADJUSTMENTS TO EARLIER FORECASTS. THERE
WILL BE A RETURN OF SOME SUNDOWNERS TO SOUTHWEST SANTA BARBARA
COUNTY TUESDAY AND WEDNESDAY EVENINGS AS ONSHORE FLOW WEAKENS
ALLOWING NORTHERLY FLOW DEVELOP ACROSS THE WESTERN PORTION OF THE
TRANSVERSE RANGE.
LONG TERM (FRI-MON)
28/201 PM.
LOOKS LIKE JUST VERY MINIMAL CHANGES LATER THIS WEEK INTO EARLY
NEXT WEEK. A FEW OF THE MODEL SOLUTIONS ARE STILL INDICATING SOME
MINOR HEIGHT RISES THIS WEEKEND, BUT THE OVERALL PATTERN REMAINS
VERY SIMILAR WITH A PERSISTENT UPPER LEVEL CYCLONE IN THE NORTHERN
BC/GULF OF ALASKA REGION RESULTING IN TEMPERATURES NEAR TO
SLIGHTLY BELOW NORMAL FOR THIS TIME OF YEAR ACROSS SOUTHWEST
CALIFORNIA. EVEN THE GFS, WHICH HAD BEEN ONE OF THE FEW MODELS
FAVORING A STRONGER RIDGE THIS WEEKEND, HAS BACKED OFF. A COUPLE
OF TROPICAL SYSTEMS ARE EXPECTED TO MOVE WEST OFF THE MEXICO COAST
AND OVER THE PACIFIC OCEAN SOUTH OF 30N. GIVEN THE WEAK BUT
PERSISTENT TROUGH ALONG THE WEST COAST THERE WILL BE NO MECHANISM
TO TRANSPORT MOISTURE FROM THOSE SYSTEMS INTO CALIFORNIA, THOUGH
WE MAY SEE AN INCREASE IN SOUTH SWELLS BY EARLY NEXT WEEK.
AVIATION
29/0224Z.
AT 2250Z AT KLAX, THE MARINE LAYER WAS AROUND 600 FT DEEP. THE
TOP OF THE INVERSION WAS AT 4500 FEET WITH A MAX TEMPERATURE OF
21 C.
HIGH CONFIDENCE IN VFR TAFS FOR DESERT SITES (KWJF AND KPMD).
LOW CONFIDENCE IN KPRB FROM 12Z TO 16Z TUE WHERE THERE IS A 10-20%
CHANCE FOR LIFR TO IFR CONDITIONS.
MODERATE CONFIDENCE IN REMAINING TAFS. ARRIVAL AND DEPARTURE OF
CIGS MAY BE OFF +/- 2 HOURS. MINIMUM CIG HEIGHT MAY BE OFF +/- 300
FT. THERE IS A 20% CHANCE FOR NO LOW CLOUDS AT KBUR/KVNY TONIGHT.
KLAX...MODERATE CONFIDENCE IN 00Z TAF. ARRIVAL AND DEPARTURE OF
CIGS MAY BE OFF +/- 2 HOURS. MINIMUM CIG HEIGHT MAY BE OFF +/- 300
FT. NO SIGNIFICANT EASTERLY WIND COMPONENT EXPECTED.
KBUR...MODERATE CONFIDENCE IN 00Z TAF. ARRIVAL AND DEPARTURE OF
CIGS MAY BE OFF +/- 2 HOURS. MINIMUM CIG HEIGHT MAY BE OFF +/- 300
FT. THERE IS A 20% CHANCE FOR NO LOW CLOUDS TONIGHT.
MARINE
28/156 PM.
HIGH CONFIDENCE IN UNSEASONABLY SMALL (BUT CHOPPY) SEAS THROUGH
TUESDAY MORNING, THEN SEAS ARE LIKELY TO BUILD TO 6-8 FEET ACROSS
THE OUTER WATERS TUESDAY NIGHT AND LAST THROUGH THE WEEK. HIGH
CONFIDENCE IN SMALL CRAFT ADVISORY (SCA) WINDS ACROSS THE OUTER
WATERS THROUGH THE WORK WEEK. ACROSS PZZ645, SCA LEVEL WINDS ARE
LIKELY DURING THE AFTERNOON AND EVENING HOURS EACH DAY THROUGH
THURSDAY. THERE IS A LOW CHANCE (25%) OF MARGINAL GALES AROUND
POINT CONCEPTION AND SOUTH TO SAN NICOLAS ISLAND WEDNESDAY
EVENING.
SCA LEVEL WINDS ARE LIKELY ACROSS THE WESTERN PORTION OF
THE SANTA BARBARA CHANNEL EACH AFTERNOON AND EVENING THROUGH AT
LEAST THURSDAY. LOW TO MODERATE CHANCE THAT SCA WINDS REACH
EASTERN PORTIONS OF THE CHANNEL THROUGH THURSDAY (MOST LIKELY
WEDNESDAY).
LOX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 PM PDT THIS EVENING
FOR ZONES 645-650. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PDT WEDNESDAY FOR
ZONES 670-673-676. (SEE LAXMWWLOX).
PUBLIC...MW
AVIATION...PHILLIPS/BLACK
MARINE...BLACK
SYNOPSIS...HALL
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