344
FXUS66 KLOX 190352
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
852 PM PDT Sat Jul 18 2026

.SYNOPSIS...18/757 PM.

Temperatures are expected to change little over the next few
days, and most areas will remain near normal. Morning low clouds
and fog will return to many coastal areas each night through
morning into early next week. A warming trend is expected by the
middle of the week, as upper level high pressure builds into the
area while onshore gradients weaken.

&&

.SHORT TERM (SAT-TUE)...18/852 PM.

***UPDATE***

Expecting similar marine layer stratus coverage along the
Central Coast tonight into the morning. Less confident in
the organization and extent of stratus across the Santa
Barbara south coast. Will have to watch if an eddy develops
and how it evolves over the Santa Barbara Channel. Stratus
is expected to cover southern portions of the LA Basin, and
unlikely to reach the San Gabriel & San Fernando valleys - at
least for a substantial period of time. The marine layer should
continue to behave similarly through the short-term period.

Temperatures will remain near normal with little fluctuation
through Monday. Followed by a warming trend Tuesday, peaking
Wednesday through Friday - with a 60% chance of heat advisories
across some interior areas. The EPS, AIFS-ENS, & GEFS ensemble
suites along with their deterministic counterparts suggest that
ridging will continue & even may strengthen some in the extended.
STDAFDLOX
Thoughts on winds and convection remain on track. Read short term
discussion below.

***From Previous Discussion***

The 500 mb heights will remain fairly similar over the region
(around 589-592 dam) through Monday as a large/wide high pressure
system persists over the Utah/Colorado/Wyoming area. Meanwhile,
Tropical Storm Elida is forecast to move northward, well off the
coast to the west, and weaken. Upper level flow will shift from
the S today to more SE on Sunday with Elida`s movements and slight
shifts in the aforementioned high pressure system.

Sunday afternoon into late Monday morning, some of the moisture
from Elida could reach the Central Coast, with the most likely
outcome resulting in an increase in mid to high clouds. However,
there is a 5-10 percent chance of a shower for the Central Coast
Sunday. At the same time, slight shifts in the high pressure
system to the NE, will help bring some monsoonal moisture from the
SE Sunday afternoon through Monday. This will result in an influx
of mid to high level clouds across the region, as well as a 5-10
percent chance of a shower or thunderstorm focused over Ventura
and L.A. County interior Mountains, mainly on Monday.

At the surface, little change in the pressure gradients will
result in similar marine layer coverage each night. The little
change in marine layer clouds, pressure gradients, and 500 mb
heights will mean little change in temperatures through the
weekend. Temperatures will generally be near normal, with highs
in the 70s to low 80s for the coast, mid 80s to mid 90s for the
valleys and lower mountains/foothills, and 90s to around 100 for
the deserts. The onset of a warming trend is expected on Tuesday,
addressed in more detail in the subsequent section.

As for winds, generally sub-advisory SW winds 25 to 40 mph can be
expected each afternoon/evening across the Antelope
Valley/adjacent foothills. Localized terrain enhancement could
result in a few areas gusting to 45 mph (i.e Lake Palmdale).
Sundowner winds in southern Santa Barbara Counties could begin to
reach near advisory thresholds on Tuesday.

.LONG TERM (WED-SAT)...18/146 PM.

The large western U.S upper level high pressure center is
forecast to drift to the area around New Mexico and the northern
Texas Panhandle by Thursday. Southwestern CA will continue to be
on the western periphery of this large upper level high, with 500
mb heights slowly increasing to 592-594 dam during the extended
period.

As a result, the flow aloft will mostly be from the SE, bringing
monsoon moisture into the region through much of the week.
Precipitable water (PWAT) values are forecast to be 1.25 to 1.50
inches through much of the week for areas south of Point
Conception and through mid-week for north of Point Conception.
These PWATs are about 150 percent of normal for this time of year.
Although the deepest moisture and is forecast to remain east of
L.A. County during the extended period, it does look like the best
chance of afternoon convection will come Wednesday and Thursday
over the mountains of at least Ventura and L.A. Counties. However,
right now chances remain around 10% for thunderstorms across the
mountains, and are too low to include in the official forecast at
this time. As we draw closer to early next week, we should have a
better idea of the chance and extent of afternoon convection for
the middle of next week.

Otherwise, it looks like varying amounts of night and morning
coastal low clouds and fog will prevail during the extended
period, with a warming trend through the middle of next week.
Moderate to high heat risk may expand into Wednesday or Thursday
as pressure gradients weaken and maybe turn lightly offshore in
the mornings with the potential for 500 mb heights building to
594-596 dam. There is a moderate chance (at least 60 percent
chance) that at least Heat Advisories will be needed in some
areas, including potentially near the coast, by Wednesday. Also of
note, Sundowner winds in southern Santa Barbara Counties could
reach near advisory thresholds into Wednesday and Thursday.

&&

.AVIATION...18/2341Z.

At 1651Z at KLAX, the marine layer was 1000 ft deep. The top of
the inversion was at 2100 ft with a max temperature of 26 C.

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

Low to moderate confidence in remaining TAFs. CIG arrival and
clearing times may be off +/- 3 hours and CIG heights off by
+/- 300 ft.STDAFDLOX

There is a 40% chance that IFR CIGs do not arrive at KSBA or KCMA.

KLAX...Moderate confidence in TAF. Arrival and clearing times of
MVFR CIGs 012-015 may be off +/- 3 hours of current forecast.
30% chance CIGs arrive as IFR 008-010 for a couple hours before
lifting to MVFR. There is a 15% chance CIGs do not arrive or
remain intermittent. No significant east wind component expected.

KBUR...Moderate confidence in TAF. 30% chance for IFR conds
between 12Z and 16Z. No wind issues expected.
STDAFDLOX
&&

.MARINE...18/757 PM.

Conditions rose to Small Craft Advisory (SCA) levels late this
afternoon with gusts of 25 to 30 knots across the outer waters and
an Advisory was issued through late tonight. Otherwise, conds are
expected to remain below SCA levels through Monday except for
localized SCA level northwest wind gusts across the Outer Waters
more than 20 NM from shore (except for near Point Conception).
Northwest winds will begin to strengthen Tuesday, rising to SCA
levels by Wednesday and likely to last through late in the week.
STDAFDLOX
A series of moderate period southerly swells will move through
the waters late Sunday through much of next week which may impact
south facing harbors, including the Port San Luis area.

&&

.BEACHES...18/757 PM.

Over the eastern Pacific, Tropical Storm Elida is forecast to
move to the west-northwest well off the Baja Coast and eventually
the California coast. Another tropical disturbance is expected to
develop in the same area and follow a slightly more westerly
track along 20 N Latitude. Both systems will produce moderate
period southerly swells. High Surf Advisories and Beach Hazards
Statements have been issued across Southwest California from
Sunday evening through Tuesday night.

The secondary system on the heels of Elida and an incoming long
period southern hemisphere south swell arriving later next week
will contribute to continued and potentially more hazardous beach
conditions into the following weekend. Additional High Surf
Advisories and/or Beach Hazards Statements are likely next week.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect from 5 PM Sunday to 11 PM PDT
      Tuesday for zones 87-354-362-366. (See LAXCFWLOX).
     Beach Hazards Statement in effect from Sunday afternoon
      through Tuesday evening for zones 340-346. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Sunday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Lund/Cohen/Black
AVIATION...Black
MARINE...Lewis/Ciliberti
BEACHES...Lewis/CC
SYNOPSIS...Lewis/Ciliberti/Cohen

weather.gov/losangeles

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