545
FXUS66 KLOX 161801 AAA
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1101 AM PDT Sun Aug 16 2026

updated aviation discussion

.SYNOPSIS...16/1259 AM.

Night through morning marine layer clouds will continue for the
coast and lowers valleys, shrinking in coverage each day into
next week. Cooler than normal temperatures continue today, then
warmer than normal temperatures return this week, with widespread
moderate Heat Risk potentially occurring away from the immediate
coast.

&&

.SHORT TERM (TDY-TUE)...16/916 AM.

Morning satellite imagery showed solid low cloud coverage north
of Point Conception, pushing well inland into the Santa Ynez
Valley. South of Point Conception, the low cloud coverage was
more disrupted, especially over the LA Basin where low clouds
were mainly confined to immediate coastal areas. The marine layer
depth continues to shrink from yesterday`s values, ranging from
2000 feet north of Point Concpetion to 1500 feet for the LA
Basin. As heights continue to build the next couple of days
and onshore pressure gradients weaken, looking for marine layer
cloud coverage to become less extensive.  The absence of cloud
coverage this morning is allowing many LA county inland areas
to warm more quickly as evident by 9 am temperatures trending
5 to 10 degrees warmer than this time yesterday.

***From previous discussion***

The warming trend is well on track through much of this coming
week, with heat likely peaking Tuesday-Thursday. 500 mb heights
will continue to increase gradually through Tuesday before
plateauing as the large area of high pressure across the Southern
United States marches westward. This combined with weakening
onshore flow will swing temperatures right back up to around 5-10
degrees above seasonal normals by Tuesday. Overnight temperatures
will increase each day as well with most areas south of Point
Conception seeing lows drop down to only the mid 60s to low 70s.
Fairly widespread moderate Heat Risk will be common away from the
immediate coastal areas starting Tuesday, with moderate chances
for fairly widespread Heat Advisories away from the immediate
coastal areas.

Marine layer clouds will likely be confined to coastal areas by
Monday/Tuesday, potentially as early as tonight. The marine layer
will help keep temperatures at immediate coastal areas moderate
during the warm up.

Northerly winds will begin increasing tonight across southwest
Santa Barbara County as well as interior mountain areas,
especially the Grapevine. While winds are expected to remain sub-
advisory levels, there is a moderate chance for winds to reach
advisory criteria in portions of southwest Santa Barbara County
Monday night. These increasing winds across southwestern SB
County may also delay or completely hinder the formation of marine
layer clouds across the south coast of the county as well as
Ventura County. If the marine layer does in fact not develop over
these areas, temperatures could be warmer than advertised.

.LONG TERM (WED-SAT)...16/114 AM.

Upper level ridging will continue to bring warm and dry
conditions to Southwest California through the work work. Onshore
flow will also be its weakest Wednesday through at least Friday.
The resulting widespread Moderate Heat Risk will also lead to a
moderate chance for heat headlines away from the coast through at
least Thursday, but increasing model agreement for Friday brings
it into play as well. The marine layer will likely be confined
just to the immediate coastal areas, and there is a small chance
that dense fog will occur as the marine layer depth will be quite
shallow.

While winds aren`t expected to be of any widespread significance,
the increasing northerly pressure gradient will allow for gusty
north to northwest winds are likely each night across the
interior mountains (especially the Grapevine), deserts, and
southwest Santa Barbara County. While widespread advisory level
winds aren`t likely in the extended period either, there is a
chance for portions of southwest SB County to reach advisory
levels. As in the short term, increasing northerly winds across
southwestern SB County could disrupt the formation of marine
layer clouds across the south coast of the county as well as
Ventura County. Again, this could result in warmer temps along the
coasts.

Next weekend still maintains some uncertainty in the evolution of
the upper pattern. Cluster analysis still shows fairly similar
chances of weak troughing setting up along the coast vs the ridge
maintaining its position out west. Suffice to say confidence from
Saturday on is fairly low. While the former solution favor a
cooling trend, the latter favor continued hot weather and even a
small chance for monsoonal convection.

&&

.AVIATION...16/1800Z.

At 1719Z at KLAX, the marine layer was at 1300 feet deep. The top
of the inversion was near 4600 feet with a temperature of 23 C.

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

Low to moderate confidence in remaining TAFs, lowest south of Point
Conception. Arrival times of IFR/MVFR conds tonight may be off
+/- 2-3 hours. Patchy marine layer may also cause conds to bounce
between VFR and MVFR/IFR later tonight and Mon morning.

KLAX...Low to moderate confidence in TAF. Arrival of cigs tonight
may be off +/- 2-3 hours from TAF with 40% chance of IFR. Cloud
coverage may bounce between SCT and OVC late tonight and Mon
morning. There is also a 20% chance no cigs late tonight. No
significant east wind component expected.

KBUR...High confidence in VFR TAF.

&&

.MARINE...16/857 AM.

Moderate to high confidence in forecast. Current Small Craft
Advisory (SCA) for gusty winds over the outer waters from near
Point Conception southward to San Nicolas Island and in the
vicinity of the Channel Islands looks on track. May see a lull in
these winds this morning, but winds will quickly increase late
this morning through the afternoon.

Good chance for SCA winds to be ongoing from this afternoon/
evening through much of the week over the outer waters, with SCA
winds expanding into the northern outer waters Monday afternoon/
evening. Tuesday and Wednesday, local gale force gusts will be
possible.

For the inner waters, SCA winds are possible during the afternoon
to evening hours for the Santa Barbara Channel today and for the
Santa Barbara Channel and inner waters north of Point Sal Monday
and Tuesday. Wednesday looks more favorable for SCA winds for the
inner waters north of Point Sal. Gusts near 25 kt are possible
for portions of the southern inner waters this evening and
possibly Monday and Tuesday evenings.

Building short period seas are expected over the next several
days, likely rising to around 7-8 feet over the outer waters.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 2
      AM PDT Monday for zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect from 6 PM this evening to 3 AM
      PDT Monday for zone 655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 AM PDT Monday for
      zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Gomberg/Lewis
AVIATION...Sirard
MARINE...Sirard
SYNOPSIS...Lewis

weather.gov/losangeles

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