549
FXUS66 KLOX 280354
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
854 PM PDT Wed Aug 27 2025

.SYNOPSIS...27/114 PM.

Showers and higher humidities are expected later tonight into
Thursday, mainly from Los Angeles County south and east, as the
remnants of Tropical Storm Juliette move through southern
California. Elsewhere, skies will be partly to mostly cloudy with
cooler temperatures. Warmer temperatures are expected over the
weekend.

&&

.SHORT TERM (WED-SAT)...27/207 PM.

Onshore flow south of Pt Conception ended up being even weaker
than expected today which resulted in temperatures that were 5-10
degrees warmer than yesterday. A few small cumulus in the LA
mountains today but not enough instability to turn into storms.

Tropical storm Juliette continues to move rapidly north along
120w, but expecting a turn to the northeast shortly as the storm
moves into westerly flow aloft associated with a weak trough along
the West Coast. Already seeing some high level clouds crossing
into the US and into southern LA County and clouds will continue
to thicken up overnight as Juliette gets closer. This is always a
tricky forecast with decaying tropical systems and whether we will
get any precipitation from it. For most of the area, even across
the Central Coast, skies will be mostly cloudy with bases at or
above 15,000 feet. Models are indicating a rather dry pattern at
lower levels and it will be difficult for rain to survive the trip
down to the surface. However, given past history with decaying
tropical systems, the deterministic models ofter underestimate
rain chances and have decided to lean strongly towards the higher
res solutions like the REFS which does indicate some light precip
across LA County and even into Ventura County, with the best
chances starting mid-morning Thursday around the Long Beach area,
then spreading north and slightly west in the afternoon. Amounts
would be light, mostly under a tenth of an inch, except possibly
up to a quarter inch in the mountains with less dry air to fall
through.

For now thunderstorms have been left out of the forecast as skies
will be mostly cloudy and storm initiation will be difficult. But
here too models often underestimate tropical systems moving into
southern California so for now the forecast is for about a 10%
chance of high based thunderstorms. The biggest concern there
would be for dry lightning striking dry brush with some areas of
humidities under 15%.

Showers chances are expected to continue into Thursday evening
then drop off by Friday morning as most of what`s left of Juliette
moves off to the northeast. Friday will be a another tricky call
with regard to temperatures as often the post-tropical environment
can still be quite warm and humid. Have bumped up temperatures a
few degrees for Friday with some valleys around 100 and coastal
areas away from the coast in the 80s and 90s. Have also added a
small chance of thunderstorms across the eastern San Gabriels
Friday afternoon.

Another warm day expected Saturday, but with decreasing humidity.
It may take a few days before stratus redevelops south of Pt
Conception.

.LONG TERM (SUN-WED)...27/203 PM.

A slight cooling trend is expected next week, though there remains
higher than normal uncertainty in the forecast beyond next Monday
as some model solutions are indicating another surge of monsoon
moisture as early as next Tuesday. Officially the forecast is for
temperatures to return back to normal levels by around mid week
with stratus making a slow return to coastal areas.

&&

.AVIATION...28/0143Z.

Around 01Z, the marine layer depth was around 800 feet deep at
KLAX. The top of the marine inversion 1500 feet with a
temperature of 24 degrees Celsius. There was another inversion up
to around 2400 feet with a temperature up to around 27 Celsius.

Low confidence in the current forecast. Higher confidence in winds
relative to ceilings. There is a moderate to high chance of LIFR
to IFR conditions at coastal terminals between 06Z and 16Z. At
terminals south of Point Conception, there is a moderate chance of
ceilings at or below 12000 feet after 09Z. There is a slight
chance of rain at terminals south of KNTD after 10Z.

KLAX...There is a 30 percent chance of IFR conditions between 09Z
and 16Z. There is a 40 percent chance of ceilings at or below
12000 feet after 09Z. There is a 15 percent of rain after 10Z.

KBUR...VFR conditions are expected through the period. There is a
30 percent chance of ceilings below 12000 feet after 07Z. There
is a 10-15 percent chance of rain after 10Z.

&&

.MARINE...27/852 PM.

High confidence in relatively light winds and small seas through
at least Friday morning, except for localized northwest wind gusts
of 20 to 25 knots from Point Conception to San Nicolas Island
each afternoon and evening. There is also some uncertainty in
winds Thursday over the waters south of the Channel Islands, and
the area could see more south to easterly winds than forecast.
High confidence in increasing northwest winds and seas beyond 20
miles from shore Friday through Labor Day Weekend.

Remnant moisture from Tropical Storm Juliette will bring a slight
chance of showers and potentially thunderstorms to the coastal
waters between San Nicolas Island and the Santa Monica Bay and
south from Thursday morning through early Friday morning. Additionally,
a southerly swell from Juliette will arrive Thursday and continue
into Saturday. A longer period but lower height southerly swell
from the Southern Hemisphere will follow and continue into early
next week. Hazardous rip currents will be common across the beach
of Ventura and Los Angeles Counties over Labor Weekend.

&&

.BEACHES...27/142 PM.

A southerly swell from Tropical Storm Juliette will arrive
Thursday and continue into Saturday. A longer period but lower
height southerly swell from the Southern Hemisphere will follow
and continue into early next week. Hazardous rip currents are
likely into next week. Elevated surf will occur along south facing
beaches in Los Angeles and Ventura Counties, especially along the
Malibu Coast.

If you are at the beach this Labor Day Weekend, swim near a
lifeguard tower and stay aware of ocean conditions.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...MW
AVIATION...Hall
MARINE...Phillips/Lewis
BEACHES...Lewis
SYNOPSIS...MW

weather.gov/losangeles

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