010
FXUS66 KLOX 031008
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
308 AM PDT Wed Sep 3 2025

.SYNOPSIS...03/259 AM.

Very warm conditions will continue through this evening, then
temperatures will lower some through the end of the week.
Monsoonal moisture will remain over the region through Thursday,
bringing risks of strong winds, brief heavy downpours, lightning,
and fire starts over Los Angeles County.

&&

.SHORT TERM (TDY-FRI)...03/259 AM.

Quite weather covers Srn CA at the moment. Skies are clear and
temps are above normal and its a little on the humid side. There
is hardly any upper flow over the area as the upper high that was
over UT ydy has weakened considerably. There is little to no
marine layer clouds this morning and also very little in the way
of mid and high level debris clouds. The extra sunshine and lack
of marine layer will bring 1 to 3 degrees of warming to most
areas. This warming along with the continued higher than normal
humidity will bring advisory level heat to most areas away from
the beaches. There is still enough moisture left in the atmosphere
(1.25" PWATs) to bring a chance of afternoon TSTMs over the VTA/LA
mtns as well as the Antelope Vly. Any TSTM that forms will move
very slowly due to the very weak steering flow and this will
enhance the potential for flash flooding. A Flash Flood Watch is
in effect for the VTA/LA mtns as well as the Antelope Vly

Things begin to settle down on Thursday. Weak flow will remain
aloft as the area will sit under the eastern edge of an E Pac
high. Hgts will fall to 588 dam about 3 dam lower than today.
There will also be a significant increase in onshore flow both to
the east and north. despite the increase in onshore flow, there
will likely not be much of any marine layer stratus in the morning
as there is just no source of lift. Most max temps will cool 3 to
5 degrees and while max temps will end up several degrees over
normal it will not be advisory level heat. It will also be less
humid making things feel even better. Just enough moisture at the
higher levels to bring a slight (20 percent) chc of TSTMs to the
mtns in the afternoon.

Hgt fall further to 585 dam on Fri. Onshore flow will continue to
increase. Low cloud will likely form across many of the coasts.
The flow will be from the west and will be dry eliminating the
TSTM threat. Most areas will cool an additional 2 to 4 degrees.
Max temps away from the beaches in the cstl areas will be in the
upper 70s to mid 80s, while the vlys will mostly end up in the
upper 80s to mid 90s.

.LONG TERM (SAT-TUE)...03/307 AM.

Benign weather on tap for the four day xtnd period. Broad troffing
will move into the western states over the weekend and then the
trof will sharpen early next week. There will be onshore flow
through the period with a moderate onshore push to the east in the
afternoons. The marine layer clouds will likely cover most of the
coasts and may xtnd into the lower vlys. But other than the
morning stratus skies should be mostly clear.

Max temps will fall another 1 to 3 degrees over most of the area
(The Central Coast will warm some as there will be weaker onshore
flow there). This cooling will bring most max temps down to 2 to 4
degrees blo normal. After Saturday`s cooling there will be little
day to day change in temps.

&&

.AVIATION...03/0621Z.

At 0515Z at KLAX, the marine layer was 800 ft deep. The top of
the inversion was near 1500 feet with a temperature of 30 C.

AT 0600Z there was a national METAR outage and there will be
limited or no amendments until obs are restored.

Good confidence in TAF from KSBA and south. Moderate confidence in
TAF for KSBP with a 30 percent chc of LIFR conds 11Z-16Z. Moderate
confidence in KSMX with a 25 percent chc of 1/4SM FG conds
09Z-15Z.

There is a 10 percent chc of a shower or TSTMs at all LA county
sites 20Z-02Z with the exception of a 20 percent chc at KPMD and
KWJF.

KLAX...Good confidence in TAF. There is a 10 percent chc of OVC004
conds 12Z-16Z. There is a 10 percent chc of a TSTM within 5SM of
the terminal from 20Z-02Z. Good confidence that any east wind
component will be under 6kt.

KBUR...Good confidence in TAF. There is a 10 percent chc of a
TSTM within 5SM of the terminal from 20Z-02Z.

&&

.MARINE...02/859 PM.

Moderate confidence in NW winds 20-25 kts across the Outer Waters
at times through the end of the week, especially in the afternoon
and evening hours. Winds will be initially strongest focused
south of Point Conception. Chances for Small Craft Advisory (SCA)
winds increase across the northern Outer Waters and nearshore
waters from Point Sal to Point Piedras Blancas by Wednesday.

For the Santa Barbara Channel and the Inner Waters adjacent to
Los Angeles and Orange Counties, Small Craft advisory level WNW
winds are again possible across the western SBA Channel to Santa
Cruz Island and from the Anacapa Pass south through the San Pedro
Channel during the afternoon to evening hours Wednesday, but look
lighter than today so there is a 40% chance for an SCA to be
issued tomorrow. Winds look stronger for the same area Thursday
afternoon and evening, with a 50-60% chance for SCA to be issued.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory remains in effect until 6 PM PDT this evening
      for zones 88-355>358-368>375-548. (See LAXNPWLOX).
     Flood Watch in effect through this evening for zones 379>383. (See LAXFFALOX).
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 9
      PM PDT this evening for zones 645-670. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Thursday for
      zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke
AVIATION...Rorke
MARINE...Phillips/Lewis
SYNOPSIS...RK/CC

weather.gov/losangeles

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