240
FXUS66 KLOX 182338
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
438 PM PDT Fri Jul 18 2025

.SYNOPSIS...18/1235 PM.

Showers and thunderstorms will be possible through Saturday for
portions of Los Angeles and Ventura Counties, with the best chance
today across Antelope Valley and the San Gabriel Mountains and
Valley. Night through morning low clouds and fog will continue for
most coasts and valleys. Below normal temperatures are expected,
with a possible warming trend late next week.

&&

.SHORT TERM (TDY-MON)...18/213 PM.

Thunderstorms are currently developing over the eastern San
Gabriel Mountains and are drifting southwest, with associated
cumulus cloud development over much of eastern Los Angeles County.
The San Gabriel Valley, eastern San Gabriel Mountains, and the
eastern Antelope Valley are at high risk of thunderstorms (or
showers) into this evening. A slight chance of storms also extends
to the Ventura County mountains, and much of LA County. Hazards
with any storms include lighting and dry lighting new fire starts,
damaging wind gusts, and areas of flash flooding, especially for
the higher elevation areas of LA County. At present, there is a
20-30 percent chance of rain rates reaching debris flow thresholds
along the Bridge Burn Scar, with lower but non-zero chances for
the Eaton Burn Scar. Please stay alert to the weather conditions
and have multiple way to receive emergency alerts (such as cell
phone, NOAA Weather Radio, or our website). As always, when
Thunder Roars --> Go Indoors!

A low pressure system to the south has shuttled moisture into the
area, and PWATs of 1.0 to 1.4 inches are widespread across the
Los Angeles Basin. Daytime heating and the expansion of the deep
mixed layer across the interior is interfacing with marine layer
moisture in the San Gabriel Valley. Pockets of surface CAPE of up
to 3000 J/kg are possible along this boundary, and likely are not
resolved in the high resolution CAMs. These factors will continue
to fuel convection into this evening. Saturday, continual
monsoonal moisture will result in linger chances of afternoon into
evening thunderstorms centered around the eastern San Gabriel
mountains and extending into the nearby foothills. By Sunday,
chances for any storms will subside as the low exits the areas and
shuts off the mositure source.

Due to the higher heat capacity of moist air, temperatures will
be a touch cooler across the normally very dry inland areas.
Temperatures will remain a few degrees below normal over the next
several days, as a result of general upper level troughing over
the region.

.LONG TERM (TUE-FRI)...18/117 PM.

High confidence in quiet weather is expected next week with
limited if any impacts. Below normal temperatures are expected,
though a gradual warming trend is possible starting on Thursday.
The cooler temperatures will be caused by a period of weak
troughing for the region as a low pressure system drifts south
from the Pacific Northwest to off the coast of far northern
California. Onshore surface pressure gradients will maintain
marine layer overnight clouds and fog across the coasts and some
valleys, as well on gusty southwest to west winds across interior
areas. Winds will be the strongest across the Antelope Valley and
adjacent foothills, and the Highway 14 corridor. Weak Sundowner
winds may also return for southwest Santa Barbara County midweek.
however all winds are likely to remain below Advisory level.

&&

.AVIATION...18/2338Z.

At 2230Z at KLAX, the marine layer depth was around 1000 feet. The
top of the inversion was 4100 feet with a temperature of 25C.

For 00Z TAF package, high confidence in KWJF, KPMD, KPRB, KBUR and
KVNY.

For coastal TAFs, only moderate confidence in 00Z TAFs. Lower
confidence due to uncertainties with how the marine layer stratus
will behave tonight with mid-level moisture moving in. Timing of
return of CIG/VSBY restrictions tonight could be +/- 3 hours of
current forecasts.

Thunderstorms over the far eastern deserts and San Gabriel
Mountains could generate gusty outflow winds through the
mountains.

KLAX...Moderate confidence in 00Z TAF. Timing of return of IFR
CIGs could be +/- 3 hours of current 06Z forecast with a 40%
chance that CIG restrictions do not develop. No significant
easterly wind component is expected.

KBUR...High confidence in 00Z TAF.

&&

.MARINE...18/157 PM.

Moderate to high confidence in the current forecast. Higher
confidence exists in the forecast for seas relative to winds.

For the outer waters, moderate to high confidence in the current
forecast. Small Craft Advisory (SCA) winds are expected for much
of the time through Wednesday night, although winds should be just
below Advisory levels for the northern waters (PZZ670) starting
Sunday with a 30% chance of SCA wind gusts at times each afternoon
and evening Sunday through Wednesday.

For the inner waters north of Point Sal, moderate confidence in
the current forecast. Winds and seas are expected to remain
generally below SCA levels through Wednesday, except for a 60%
chance of SCA wind gusts Saturday night, and a moderate (30%)
chance of SCA level winds during the afternoon and evening hours
Sunday through Wednesday.

For the inner waters south of Point Conception, moderate
confidence in the current forecast. There is a low- to- moderate
(20-30 percent) chance of SCA level winds through Wednesday
evening, except for a moderate (40-50 percent) chance of SCA level
winds across the western half of the Santa Barbara Channel on
Saturday evening.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Sunday for zone
      670. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Monday for
      zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Schoenfeld/Schoenfeld/RM
AVIATION...RAT
MARINE...Sirard
SYNOPSIS...Schoenfeld

weather.gov/losangeles

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