781
FXUS66 KLOX 210353
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
853 PM PDT Thu Aug 20 2026

.SYNOPSIS...20/438 PM.

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 Friday through the weekend.

&&

.SHORT TERM (THU-SUN)...20/821 PM.

A persistent ridge of high pressure remains more or less centered
over the four corners region, with higher 500 mb heights at times
extending westward over southern California. This will continue to
maintain above normal temperatures across the area, and will also
allow monsoonal moisture to move into the area from the southeast.
Surface gradients remain weak to moderate, with onshore gradients
from LAX to Daggett currently around +4 mb, and northerly
gradients between KSMX and KSBA.

Highs today were between 100 to 105 for the interior, including
Woodland Hills at 104 degrees. From the coast to coastal valleys
highs were in the 70s to low 90s. Most areas have been between 5
to 10 degrees above normal. A few degrees of cooling are expected
on Friday, with little change on Saturday, then an uptick on
Sunday. The Heat Advisories in effect for interior sections will
be allowed to expire this evening, however warm conditions will
continue and the slight increase in monsoonal moisture will add to
this effect.

Moderate gusty onshore winds are affecting the interior passes and
canyons into the Antelope Valley this evening, with gusts up to
around 35 mph. At the same time, the northerly gradients are
causing Sundowner wind gusts to around 25 mph across southwest
Santa Barbara County. High resolution models show the winds
decreasing after 03Z, so expect that winds are near their peak
now, with decreasing speeds through late in the evening.

Finally, there is a slight chance of showers and thunderstorms
over portions of LA County, especially from the
foothills/mountains to the Antelope Valley, and also over eastern
interior Ventura County. The timing will be late this evening
into Friday morning. There is a weak disturbance in southeast
flow created by the position of the ridge aloft, and some
monsoonal moisture moving into the area. While the mid level
moisture likely to remain over the area through Friday night, the
disturbance will shift out of the area by Friday 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.

.LONG TERM (MON-THU)...20/112 PM.

For the extended, a rather stagnant pattern is expected. At upper
levels, high will remain centered over Arizona and New Mexico
through the period with little change in H5 heights over
Southwestern California. Models continue to exhibit some
differences at the surface with the ECMWF indicating weak diurnal
gradients while the GFS indicates weak to moderate onshore
gradients.

Forecast-wise, only minor day-to-day changes are expected in the
sensible weather. There will be some slight cooling on Monday, but
then some warming in the Tuesday-Thursday time frame. 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. Also, 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 Sundowner winds can be expected
across southern Santa Barbara county each night, mainly around
the Gaviota and Refugio areas. It will not be out of the question
to see some wind products for these northerly wind-prone areas
sometime next week.

As for clouds and precipitation chances, the area will remain on
the periphery of any monsoonal moisture. 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 cause "fits" with regard to
areal coverage, but many coastal areas will continue to deal with
night/morning stratus and fog.

&&

.AVIATION...20/2331Z.

At 2232Z at KLAX, the marine layer was 700 feet deep. The top of
the inversion was at 2000 feet with a temperature of 29 C.

High confidence in VFR TAFs for KPMD, KWJF, KBUR, KVNY, & KPRB.

Good confidence in TAF for KSBP and KSMX as timing of flight cat
changes may be off +/- 2 hours of forecast. Cig height may be off
+/- 200 feet.

Fair confidence in TAF for KOXR and KCMA. There is a 30% chance
of LIFR/IFR CIGs from 21/08Z-16Z.

For LAX and LGB, arrival and clearing times of CIGs may be off
+/- 2 hours of current forecast. Cig height may be off +/- 200
feet. 30-40% chance of no low clouds.

There is a 30% chance of SHRA at KPMD and a 20% chance at KWJF
from 21/09-16Z.

KLAX...Fair confidence in TAF. Arrival and clearing times of
CIGs 006 (+/- 200 ft) may be off +/- 2 hours. There is a
40% chance of no low clouds. There is a 5-10% chc of -SHRA
21/05Z-11Z.

KBUR...High confidence in TAF. No wind issues expected.

&&

.MARINE...20/647 PM.

Moderate to high confidence in periods of Small Craft Advisory
(SCA) level winds (20-30 knots) across the Outer Waters each
afternoon and evening into next week, thus a long duration SCA has
been issued through Sunday morning. This may need to be extended
into next week as we progress through the weekend. Local gusts of
20-25 kt will be possible across the nearshore waters along the
Central Coast through Friday, then there is a moderate chance for
more widespread wind gusts reaching 25 knots starting Saturday.

Aside from gusts of 20-25 knots reaching the western half of the
Santa Barbara Channel each afternoon/evening starting Friday,
widespread SCA conditions are not likely across the nearshore
waters south of Point Conception. Localized gusts near 20 knots
are possible near Point Dume and the San Pedro Channel during the
afternoon through early evening hours starting Friday. Winds may
pick up in strength a bit early next week, with low to moderate
chances that conditions become widespread enough to warrant an
advisory.

&&

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

&&

$$

PUBLIC...Thompson/Ciliberti
AVIATION...Black
MARINE...Lewis/Black
SYNOPSIS...Gomberg/Ciliberti

weather.gov/losangeles

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