333
FXUS66 KLOX 202332
AFDLOX

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

UPDATED AVIATION SECTION

.SYNOPSIS...20/306 AM.

Night through morning marine layer clouds will be confined to the
coastal areas, mostly north of Pt Conception, through much of
this week. Warm conditions are expected away from the immediate
coast slight cooling is forecast Friday through the weekend.

&&

.SHORT TERM (TDY-SUN)...20/112 PM.

Overall, 12Z models in good synoptic agreement through the short
term period. At upper levels, high will "wobble" around the 4
Corners through Friday, before drifting southeast across New
Mexico. At the surface, moderate onshore flow will continue to the
east with some weak northerly offshore flow.

Main concern in the short term will continue to be the heat. Based
on current trends, today will be the hottest day in the short term
period. So, current HEAT ADVISORIES for interior sections still
looks good through this evening. For Friday, there is expected to
be some slight cooling across most area with some slight decrease
in thicknesses and more extensive mid-level clouds. There will be
a slight uptick in humidity on Friday which will counteract the
slightly cooler temperatures. For Saturday and Sunday, near
persistent temperatures are expected with most areas away from the
coast remaining 5-10 degrees above seasonal normals. Looking at
Heat Risk grids, the moderate areas decrease in areal coverage on
Friday. So, at this time, will not extend the HEAT ADVISORIES
through Friday. Although no additional advisories are expected,
residents should still exercise caution this weekend in this above
normal heat.

Secondary concern in the short term period will be the possibility
of some showers and thunderstorms. With SE-S flow aloft, there
will be an increase in PWATs tonight and Friday. Models indicate a
weak disturbance moving across Ventura/LA counties late tonight
which could generate some isolated showers and thunderstorms. By
Friday afternoon, this disturbance will be out of the area, but
there will still be enough moisture around to warrant a slight
chance of afternoon showers and thunderstorms over the eastern San
Gabriel Mountains and the northern Ventura county mountains. Any
thunderstorms that may develop will likely not produce much rain,
resulting in gusty outflow winds and dry lightning as the main
hazards. 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.

Finally with respect to winds, there will continue to be some
northerly offshore gradients through the weekend. So, there will
be locally gusty north winds across the western half of the Santa
Ynez Range, but any advisory-level winds will remain localized
around the Gaviota and Refugio areas.

.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...20/1152 AM.

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 today, then there is a moderate chance for more
widespread wind gusts reaching 25 knots starting Friday.

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.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory in effect until 8 PM PDT this evening for zones
      38-88-343>345-351-353-371>373-375-376-379-380-548. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 9 AM PDT Sunday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

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

weather.gov/losangeles

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