252
FXUS66 KLOX 211931
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1231 PM PDT Fri Aug 21 2026

***UPDATED AVIATION AND MARINE SECTIONS***

.SYNOPSIS...21/357 AM.

Night through morning marine layer clouds will be confined to the
coastal areas, mainly along the Central Coast, through much of
this week. Warm conditions are expected away from the immediate
coast. Slight cooling is forecast today with increased humidity.

&&

.SHORT TERM (TDY-SUN)...21/116 AM.

The upper level high centered around the four corners is bringing
southerly, monsoonal flow to southern California. Already, a
cluster of showers have formed southeast of Los Angeles County,
and they may reach LA and Ventura Counties early this morning.
Shower and thunderstorm chances last into this afternoon, focused
over the interior mountains. There is a weak disturbance in
southeast flow created by the position of the ridge aloft that
could help initiate convection, and while the mid level moisture
likely to remain over the area through tonight, the disturbance
will shift out of the area by this afternoon so precip chances
will decrease through the day (from 10-20 percent to around 10
percent). Any thunderstorms that may form will likely not produce
much rain, but may produce gusty outflow winds and dry lightning.
For Saturday/Sunday, the mid- level moisture will decrease and
there will only be a 5-10% chance of afternoon showers and
thunderstorms over the higher terrain.

Heights are forecast to be around 593-594 mb through Saturday
before the high begins slowly advancing east, translating to
above normal temperatures across the area. Surface gradients
remain weak to moderate, with onshore gradients from LAX to
Daggett peaking around +3 to +4 mb, and northerly gradients
between KSMX and KSBA.

Expecting highs today between 97 to 104 for the interior, 90s for
the coastal valleys, and 70s to 90 degrees for the coastal
plains. In general, warm temperatures will continue through the
weekend, with increased humidity due to moist monsoonal flow.
Expect to see a bit of cooling today with the potential for some
additional clouds, little change on Saturday, then a little uptick
in temperatures on Sunday.

Gusty onshore winds are expected again for this afternoon and
evening over the Antelope Valley and valley foothills, with gusts
around 35 to 40 mph are possible for this afternoon and evening.
There will be a weakening trend Saturday into early next week.
Sub advisory level Sundowner winds will reoccur each evening
through the weekend, possibly reaching advisory levels by Monday
evening.

.LONG TERM (MON-THU)...21/352 AM.

For the extended, a rather stagnant pattern is expected. At upper
levels, southwestern California remains on the western edge of the
high pressure, which shifts slightly from centered over the Texas
New Mexico border to the Arizona New Mexico border. Not seeing
significant changes in day to day heights, so warm weather should
persist. The onshore LAX-DAG pressure gradient continues to trend
weaker through Tuesday, but is forecast to strengthen somewhat
mid-week.

Forecast-wise, only minor day-to-day changes are expected in the
sensible weather. There will be some warming Tuesday-Wednesday,
so, areas away from the coast will generally remain 5-10 degrees
above seasonal normals. Depending on how things develop, there is
a chance of some heat products being needed next week. There is a
significant spread in the model gradients, so confidence is lower
in terms of the strength of the onshore flow. If the ECMWF is
correct with the weak diurnal pressure gradients, then high
temperatures could be warmer than currently forecast.

As for winds, there will continue to be some weak northerly
offshore gradients. So, continued northerly Sundowner winds can
be expected across southern Santa Barbara county each night,
mainly around the Gaviota and Refugio areas. Tuesday evening
currently has the best chance for wind advisories, but cannot rule
out Monday or Wednesday evenings as well.

As for clouds and precipitation chances, the area will remain on
the periphery of any monsoonal moisture. Upper level flow is
forecast to shift more southwesterly as early as Saturday, so,
any convection will likely remain south and east of the district,
but there will still be a 5-10% chance of afternoon convection
over the mountains. The marine layer will likely continue to be
patchy in areal coverage (especially south of Point Conception),
but many coastal areas will continue to deal with night/morning
stratus and fog.

&&

.AVIATION...21/1930Z.

At 18Z at KLAX, the marine layer was 600 feet with an inversion
top at 3300 feet and 27 Celsius.

High confidence in VFR conditions through at least Saturday for
KPRB, KSBA, KVNY, KBUR, KPMD, KWJF. There is a 5-10% chance of
-TSRA at KPMD and KWJF today.

Chances for LIFR/IFR ceilings tonight at KSBP (80%) KSMX (100%)
KOXR (10%) KCMA (20%). Chances for IFR/MVFR ceilings tonight at
KSMO (10%) KLAX (20%) KLGB (20%).

KLAX...Other than a 20% chance of BKN008-012 from 10-16Z Saturday,
high confidence in VFR conditions through at least Saturday. High
confidence in any east winds staying under 6 knots.

KBUR...High confidence in VFR conditions with seasonal winds
through at least Saturday.

&&

.MARINE...21/1224 PM.

High risk of Small Craft Advisory (SCA) conditions continuing
over the outer waters from the Central Coast to San Nicolas Island
through Saturday night, lowering to moderate for Sunday and
Monday. There is a moderate risk for the nearshore Central Coast
waters each afternoon and evening through Saturday, lowering for
Sunday and Monday. Elsewhere, the risk for SCA is low, with
seasonal winds likely.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 2 AM PDT Saturday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 AM PDT Sunday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Phillips/Ciliberti
AVIATION...RK
MARINE...RK
SYNOPSIS...LP/Gomberg/Ciliberti

weather.gov/losangeles

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