535
FXUS66 KLOX 050304
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
804 PM PDT Fri Sep 4 2026

.SYNOPSIS...04/225 PM.

Tropical Cyclone Marie, which will remain well offshore of SoCal,
will bring impacts to the region over the weekend into early next
week. Rain is favored late Saturday and Sunday focused over Los
Angeles and Ventura Counties. Increasing southerly swell will
create hazardous surf conditions at the coasts.

&&

.SHORT TERM (FRI-MON)...04/703 PM.

***UPDATE***

A small-scale perturbation on the eastern peripheral of Hurricane
Marie will move northward due to mainly the interaction of large-
scale troughing situated along the west coast. This activity is
expected to arrive later Saturday into Sunday. Widespread light
rain showers with areas of heavier rainfall is likely especially
under any thunderstorm (5-15% chc) that develops. The best chc for
numerous rain showers is across LA county. Generally expecting
rainfall amounts under 0.25" across LA/VTA counties. Cannot rule
out rainfall totals of 0.50"-0.75" in a few local spots.

Interestingly enough, a few CAMs are indicating that a "dry-slot"
may develop across Ventura county which could reduce rain shower
coverage a bit. This does seem like a reasonable possibility due
to the eastward location of the aforementioned perturbation, and
the well-defined shortwave rounding the base of the trough on
Sunday. Not perfect timing and moisture profiles are somewhat
limited over eastern SB county, but this may result in a better
chance for showers and thunderstorms across that area. But
confidence is still pretty low as short term guidance is bouncing
around trying to handle this feature. Thus, have not made any
significant chances in POPs across VT and SB counties. Still want
to emphasis that confidence is pretty good with current
precipitation forecast across LA County.

Have reduced high temperatures about 5 degrees across LA county
due to widespread showers and cloud cover. Good consenus across
guidance that LA Basin will likely struggle to get out of the low
80s on Sunday.

***From Previous Discussion***

Hurricane Marie is currently 950 NM due south of Los Angeles, and
is forecasted to travel in the northwest direction over the next
several days. Marie will remain well offshore of the California
Coast, but will still be able to send some weather impacts to
SoCal. The most significant hazards from Marie will be seen across
the beaches where very hazardous ocean swimming conditions are
expected for the Labor Day holiday weekend. Potentially deadly rip
currents and high surf is expected for south-facing beaches.
Please consider swimming near a lifeguard and follow their
guidance. Additionally, moderate coastal flooding and coastal
erosion is expected for vulnerable south-facing beaches. See the
beaches section below for details on the coastal hazards.

As for the weather conditions over land, expect increased cloud
cover, elevated humidity and periods of light to moderate rain.
Rain will be possible as early as late Saturday, becoming likely
(50-70% chance) at least for Los Angeles County early Sunday
morning into Sunday night, with lower chances to the north.
Mositure from Marie will funnel into the area along the bottom of
a broad upper level trough, and PWATs may approach 2 inches in
portions of the region. Lapse rates aloft however limit some of
the convective potential, so despite the extremely anomalous
amount of moisture rain totals are likely to mostly 0.25 inches
or less, except for local amounts of 0.50 to 0.75 inches possible
in Los Angeles and Ventura County (especially foothills) and near
thunderstorms or heavier showers. There is a 5-15% chance of
thunderstorms on Sunday focused over Los Angeles County. One
impact of note is that roads will be quite slick with any wetting
rainfall due to the build up of oils over the last several months.

Temperatures will feel warmer over the weekend with the additional
humidity but still remain within a few degrees of normal.
Overnight lows could be quite warm and only into the 70s for our
southern coasts and coastal valleys where the topical mositure
will be the greatest. Monday temperatures will warm a few more
degrees but humidity and rain chances will decrease.

.LONG TERM (TUE-FRI)...04/232 PM.

In the long term, there is uncertainty in the upper level
pattern, especially mid week onward. Tuesday, there is moderate
confidence in 500 mb heights rising over the region, along with
continued warming temperatures to a few degrees above normal at
the coasts and coastal plains, and a few degrees below normal
farther inland. By Wednesay, Southwest California may become
sandwiched between a ridge to the southeast and a trough (that
will have entrained moisture from the remnants of Marie) to the
west. This will keep the door open for additional tropical
moisture. The associated southwest flow aloft may bring unsettled
weather, although timing, location, and potential impacts are
uncertain that far out.

&&

.AVIATION...05/0108Z.

At 2343Z at KLAX, the marine layer was 1500 feet deep. The top of
the inversion was 3000 feet with a temperature of 22 deg Celsius.

High confidence in desert TAFs. Moderate confidence in remainder
of TAFs. MVFR conds are possible at KPRB 12-17Z Sat. Cigs could
return to KSBP and KSMX as early as 03Z Sat, and brief,
intermittant MVFR conds are possible at KOXR, KCMA, KBUR, and KVNY
06-17Z Sat. There isa 30% chance of no cigs forming at KSMO,
KLAX, and KLGB, or cigs are brief/intermittent through the night.

KLAX...Moderate confidence in TAF. Timing of return of MVFR CIGs
could be +/- 3 hours of current 11Z forecast. There is a 30%
chance that CIG/VSBY restrictions do not develop overnight. No
significant easterly wind component is expected.

KBUR...Moderate confidence in TAF, with a 20% chance of
brief/intermittent CIGs of BKN0010-022 between 08-17Z Sat.

&&

.MARINE...04/741 PM.

For the Outer Waters, moderate confidence in current forecast.
Tonight through Saturday night, there is a 20-30% chance of Small
Craft Advisory (SCA) level winds. For Sunday, there is a 60-80%
chance of SCA level winds. For Monday through Wednesday, there is
a 30-40% chance of SCA level winds.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Today through Saturday, high
confidence in winds and seas remaining below SCA levels. On
Sunday and Monday, there is a 30-40% chance of SCA level winds
in the afternoon and evening hours. For Tuesday and Wednesday,
high confidence in winds and seas remaining below SCA levels.

For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. For a majority of the southern
Inner Waters, high confidence in winds and seas remaining below
SCA levels today through Wednesday. The only exception will be
the western half of the Santa Barbara Channel where there will be
50-60% chance of SCA level winds late Sunday afternoon and
evening.

Tropical moisture will stream over the area Sunday through
Tuesday, bringing the threat of showers to the coastal waters.
There is a 15% chance of thunderstorms Sunday afternoon for the
waters south of the Channel Islands. A large southeast to south
swell will also impact the area, causing increased currents and
surges in the vulnerable harbors.

&&

.BEACHES...04/740 PM.

Significant coastal impacts are expected across Southern
California beaches this Labor Day weekend. A large southeast to
south swell from Hurricane Marie will move into the coastal
waters this weekend with swell heights of 5-8 feet and a period
around 13 seconds.

High surf conditions are expected on south-facing beaches of
Ventura and Los Angeles counties, peaking at 5-8 feet with local
sets to 10 feet on Sunday and Monday. The Santa Barbara South
Coast will be largely protected from this swell, but there are
some small windows of southeasterly and southwesterly energy that
could cause boosts in the waves. HIGH SURF ADVISORIES remain in
place for Los Angeles and Ventura Counties, with BEACH HAZARDS
STATEMENTS (a step below high surf advisories) in effect for Santa
Barbara and San Luis Obispo Counties.

High tides will also be increasing through early next week. Due to
a variety of reasons, the actual observed tides have been running
6 inches above predictions for sometime now. The south swell will
likely boost that enhancement. As a result, high tides should
exceed 7 feet by Monday. Adding large tides with the south swell
will result in a moderate risk for coastal flooding over the
vulnerable south-facing shores. Areas of most concern include
Avalon, Long Beach (Alamitos Peninsula), and Oxnard to Malibu
(including Point Mugu). COASTAL FLOOD ADVISORIES remain in effect
for Los Angeles and Ventura Counties where the best combination of
tides and waves will occur, but Santa Barbara and San Luis Obispo
Counties could also see some isolated issues.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory in effect from 6 AM Saturday to 11 PM
      PDT Tuesday for zones 87-354-362-366. (See LAXCFWLOX).
     High Surf Advisory in effect from 6 AM Saturday to 11 PM PDT
      Tuesday for zones 87-354-362-366. (See LAXCFWLOX).
     Beach Hazards Statement in effect from 6 AM PDT Saturday
      through Tuesday evening for zones 340-346-349-350. (See LAXCFWLOX).
PZ...NONE.

&&

$$

PUBLIC...Schoenfeld/Black
AVIATION...KL
MARINE...RAT/KL
BEACHES...RAT
SYNOPSIS...Lewis/RS

weather.gov/losangeles

Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox

NWS Los Angeles (LOX) Office