Area Forecast Discussion
Issued by NWS Los Angeles, CA
Issued by NWS Los Angeles, CA
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FXUS66 KLOX 091202
AFDLOX
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
402 AM PST Sun Nov 9 2025
.SYNOPSIS...09/100 AM.
A warming and drying trend will continue into Monday as a ridge of
high pressure continues to build aloft and the offshore flow at
the surface continues. Temperatures above seasonal levels are
likely through Monday, with highs in the 80s and 90s across most
coastal and valley locations. A storm system will likely move
over the region during the latter half of next week and could
bring moderate to heavy rainfall.
&&
.SHORT TERM (TDY-TUE)...09/334 AM.
High pressure aloft will continue to build over SW CA through
Monday before weakening and shifting eastward on Tuesday. As the
high pressure builds, the offshore gradients will continue to
strengthen a little bit through Monday morning.
Currently, marine layer clouds are stretching all across the
coasts of the four counties, with some some clouds sneaking into
the San Gabriel Valley, a small patch in the eastern San Fernando
Valley (right over Burbank airport), and into the Ventura County
inland Coast (and up to the top of the Conejo Grade). While a
Dense Fog Advisory is in place until 9 AM for the Malibu Coast as
well as the Ventura Coast and Inland Coast, the rest of the
coastal and inland coastal areas may see areas of patchy dense fog
down to a quarter mile visibility or less. As for tonight, marine
layer clouds may make a return to the coasts if the offshore flow
remains weak enough, and patchy dense fog will be possible again
into Monday morning anywhere these clouds may form. Otherwise,
skies are expected to clear through Monday. By Tuesday morning,
there will be the chance of some stratus/fog returning to coastal
areas. Please slow down and leave a larger gap for the vehicle in
front if dense fog is encountered while driving.
As for temperatures, a warm up across the region is still expected
these next two days thanks to the ridge of high pressure aloft and
the offshore flow. High temperatures are expected to reach into
the 80s to 90s by Monday, with a little bit cooler temperatures at
the immediate coasts. These temperatures will be around 10-15
degrees above normal for this time of year. Some locations
will approach record highs, but do not anticipate any record
breaking readings. One caveat, however, is if the offshore
gradients end up being weaker than the models are forecasting,
which would result in cooler temperatures, especially across the
LA Basin. Overnight lows will also be warm, especially across the
foothills and valleys.
As for winds, the offshore flow is on the weaker side this
morning (around -2 mb for both offshore LAX gradients), with the
pressure gradients forecast to reach around -4.0 and -2.6 mb
(LAX-DAG and LAX-BFL, respectively) Monday morning. The offshore
flow, with weak upper level support and lack of cold air
advection, will result in a weak (maybe barely moderate) Santa Ana
event, with gusty winds across the typical Santa Ana Corridor of
Ventura and Los Angeles Counties as well the Santa Lucias this
morning and tonight into Monday morning. Expecting winds to
remain below advisory levels, with a isolated mountain locations
reaching around 45 mph.
.LONG TERM (WED-SAT)...09/334 AM.
Overall for the extended period, models continue to be on the
same synoptic page with a wet and unsettled period of weather.
Unfortunately, there still are still differences in the details
(timing, amounts, etc.), so not much change in the forecast at all
for the extended.
On Wednesday, increasing clouds and cooler temperatures can be
expected as storm system approaches the West Coast. Some light
warm frontal precipitation will be possible Wednesday evening,
ahead of the storm.
For Thursday and Friday, both the deterministic GFS/ECMWF and
their respective ensembles indicate a storm will roll across the
area and will bring significant measurable rainfall to the area.
However, the ECWMF and its ensembles (as well as the ECWMF-AIFS)
are slower with the progression of the system and generate more
significant rainfall than the GFS and its respective ensemble
members. With these differences, confidence in the forecast
details remains on the low to moderate side. Current best forecast
estimate is for a widespread 1-2 inch rain event across coasts and
valleys, and 2-4 inches across mountains and foothills. As
mentioned before, there is quite a wide range across model
outcomes, so there remains a 30% chance of a lesser event, or
a heavier event including some convective potential. As for rain
rates and specific burn scar concerns, it really depends on the
tilt of the trough, direction of flow, and the convective
potential, so it is still too early to come up with reasonable
rain rates. Additionally, based on thicknesses, snow level look
like they could drop to around 6000 feet and the resorts could see
some decent snow accumulations. However, much like with rain
totals, confidence in the exact snow levels remain on the low to
moderate side. By late Monday or Tuesday, the window for the
higher resolution models opens up, so hoping by Tuesday, there
will be more model agreement and details can be fine tuned.
&&
.AVIATION...09/1201Z.
At 0753Z at KLAX, the marine layer was 800 feet deep. The top of
the inversion was 2300 feet with a temperature of 25 C.
High confidence in TAFs for desert airfields (KPMD & KWJF).
Overall, low to moderate confidence in 12Z TAF Package.
In general, expecting V/LIFR to low IFR conditions for coastal
sites roughly through 18Z Sunday. Timing of CIG/VSBY restrictions
may be off +/- 2 hours and flight cats could be off one or two
when CIGs are present.
KLAX...Moderate to low confidence in TAF. LIFR to IFR conditions
expected through around 19Z Sunday (+/- 2 hours). There is a 10%
chc of no clearing through 12Z Monday. If clearing does occur,
there is low confidence if LIFR CIGs OVC002-004 return around 03Z
Monday. Good confidence in MVFR or VFR conditions after 12Z Mon.
There is a 15% chance that east wind component reaches 7-8 kts
after 12Z Monday.
KBUR...Moderate confidence in TAF. MVFR VSBYs with BR through 15Z
Sunday (+/- 2 hours). Then, VFR conditions expected.
&&
.MARINE...09/402 AM.
Seas are below Small Craft Advisory (SCA) levels across all the
outer waters. 10-15 knot E to NE winds will be common early Sunday
morning through Monday afternoon nearshore from Ventura to Point
Dume. Local wind gusts could reach 21 kts near Pt. Mugu during the
early morning hours on Sunday & Monday (30% chance). Otherwise,
relatively mild conditions will continue into at least Tuesday.
Moderate to high confidence that a storm system will approach the
Coastal Waters as early as Wednesday night, bringing rain and at
least Small Craft Advisory level winds and large steep and choppy
seas to the region, including nearshore. There is a potential for
Gale Force Winds. Confidence is low in timing and magnitude of
impacts.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Dense Fog Advisory in effect until 9 AM PST this morning for
zones 354-355-362. (See LAXNPWLOX).
PZ...NONE.
&&
$$
PUBLIC...Thompson/Lund
AVIATION...Black
MARINE...Black/Schoenfeld
SYNOPSIS...Hall/KL
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox