508
FXUS66 KLOX 012058
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
158 PM PDT Wed Oct 1 2025

.SYNOPSIS...01/158 PM.

A series of weak disturbances will keep a persistent night through
morning low clouds pattern going across most of the coasts and
some lower valleys through Friday. Weak offshore flow will bring
mostly sunny skies to the area for the weekend. Afternoon high
temperatures will continue to run below normal through the period.

&&

.SHORT TERM (TDY-SAT)...01/158 PM.

Synoptically, the area is in a trough from an upper level 533 dam
Low in the Gulf of Alaska. Central and northern California saw
some rain today, but it stayed north of our area. By Friday the
Low will have deepened to about 562 dam and moved over northern
California, bringing a very low chance of rain to the northern
part of our area. By Saturday the system has moved east to Utah,
but then the trough takes on a positive tilt and moves back over
the area through early next week.

Most of the area was up 3-5 degrees today with rising heights, with
the exceptions in stratus-covered areas along the coast. Still
expecting a little better marine layer cloud coverage tonight
along the coasts as the marine inversion reforms and the marine
layer shrinks. Onshore flow is on the weak side so the vlys
(except the Santa Ynez) will remain clear. The SBA south coast
will also be clear as another sub-advisory level Sundowner will
keep the clouds away.

Hgts and pressure gradients do not change much and Thursday will
be a very similar day compared to today. Increasing N flow to SW
SBA county expected Thursday night into the predawn hours Friday
and Sundowner Winds are likely to reach advisory-level strength.

Friday will be cooler and breezy in the wake of the dry trof. Look
for gusty wind in the mtns and Antelope Vly as well as increased
sea breezes at the csts. Hgts fall to 578 dam and this will cool
the cst/vlys (along with the increased sea breeze) by 2 to 4
degrees. Even more cool air advection across the interior will
lower max temps by 4 to 8 degrees. Max temps will end up 5 to 10
degrees blo normal. Friday night looks like the windiest of the
next three with gusty advisory winds across the SBA south coast,
the I-5 corridor and western portions of the Antelope Vly. Light
rain is not inconceivable in the northern portion of the area on
Friday as the Low moves closer.

On Saturday the area will be under the western portion of the
departing trof with strong NW flow aloft. At the sfc weak offshore
flow will develop from the east and mdt offshore flow will come
from the north. The offshore flow and mixing from the trof should
be enough to thwart the marine layer and skies will be mostly
clear. There will be some weak N to NE winds in the morning.
Rising hgts and the weak offshore flow will team up to bring 2 to
4 degrees of warming to most areas. Saturday will likely be the
windiest day of the next few.

.LONG TERM (SUN-WED)...01/158 PM.

Medium range mdls are in good agreement for the Sunday forecast
calling for a long wave pos tilting trof to set up over CA. At
the sfc onshore flow will return as will the coastal low clouds.
The switch to onshore flow will cool the csts/vlys by a few
degrees, while the interior continues to warm some.

On Monday the trof axis will move southward and be directly over
Srn CA. Onshore flow will increase both to the N and E. Lower hgts
and the increased onshore flow will bring noticeable cooling of 3
to 6 degrees to the area. Max temps across the csts/vlys will
only be in the upper 60s and 70s or 6 to 12 degrees blo normal.

Some warming is forecast for Tuesday and it could certainly be very
similar to Monday. More warming on Wednesday as heights continue
to rise.

&&

.AVIATION...01/1845Z.

At 18Z at KLAX, the marine inversion was around 1500 ft deep. The
top of the inversion was around 2600 ft with a temp of 17 deg C.

High confidence in TAFs for desert airfields (KPMD and KWJF).

Moderate confidence in remaining TAFs. VFR conds are expected into
this evening except later tonight in the vlys. For tonight into
Thu, timing of CIG/VSBY restrictions may be off by +/- 3 hours &
flight minimums may be off by one category from current forecast.
Cigs may bounce between categories at times.

KLAX...Moderate confidence in TAF. Arrival and clearing times of
CIGs may be off by +/- 3 hours. OVC012 is expected to be the
lowest possible cig overnight, and no significant east wind
component is expected.

KBUR...Moderate confidence in TAF. Flight cat changes late
tonight may be off +/- 2 hours.

&&

.MARINE...01/105 PM.

For the outer waters, there is moderate to high confidence in the
current forecast. Winds and seas will remain below Small Craft
Advisory (SCA) levels through Thursday, then winds will increase
to SCA levels Thursday night and continue through Saturday night.
There is also a 30%-40% chance of Gale Force winds Friday
afternoon and Friday night, especially from around Point
Conception southward. Conds are then expected to be below SCA
levels Sunday through Monday night.

For the inner waters north of Point Sal, there is moderate to
high confidence in the current forecast. SCA level wind gusts at
times are expected mainly afternoon and evening hours Friday and
Saturday. Otherwise, conds will be below SCA levels through Monday
night.

For the inner waters south of Point Conception, there is moderate
to high confidence in the current forecast. In the Santa Barbara
Channel, winds and seas are expected to reach SCA levels at times
Thursday night through Saturday night, with a 30% chance of Gale
Force wind gusts Friday night over the western part of the
channel. SCA level winds and seas are also expected for the
southern inner waters Friday afternoon and Friday night.
Otherwise, conds are expected to be below SCA levels through
Monday night.

&&

.BEACHES...01/236 AM.

Southerly swell generated by Tropical Cyclone Narda may linger
through today, with a risk of elevated surf and rip currents
continuing for south-facing beaches (especially along the Malibu
Coast).

&&

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

&&

$$

PUBLIC...Rorke/jld
AVIATION...Sirard
MARINE...Sirard
BEACHES...Schoenfeld
SYNOPSIS...JLD

weather.gov/losangeles

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

NWS Flagstaff Office