790
FXUS66 KLOX 210922
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
222 AM PDT Tue Apr 21 2026

.SYNOPSIS...21/222 AM.

Light to moderate rain is expected through today, although
locally heavier rain is possible over the northern area. The
highest rain amounts are expected for San Luis Obispo County,
however with minimal impacts. Much cooler weather is on tap
through Wednesday. Gusty southwest winds are expected today,
followed by west to northwest winds Wednesday through Friday.

&&

.SHORT TERM (TDY-THU)...21/221 AM.

A moderate late season storm will move across Southwest California
through today. Most of the rain will occur this morning through
this evening, however some light showers may linger over the
northern mountain slopes tonight into early Wednesday. The
highest rain amounts will cover San Luis Obispo and Santa Barbara
Counties, as the front will weaken as it moves over Ventura County
and especially Los Angeles County. There will be a slight chance
of thunderstorms from 400 AM today through the afternoon hours
over San Luis Obispo County. While there is a chance of locally
heavier rain at times across much of the area, this will be
enhanced over SLO county due to the convective chances.

Rainfall totals will range from one quarter of an inch to around an
inch for San Louis Obispo (except for 1.5-2 inches for the coastal
hills) and Santa Barbara Counties, to 0.5 inch in the Ventura
Mountains, to one third of an inch or less elsewhere. Brief
heavy downpours, gusty winds up to 40 mph, and cloud-to- ground
lightning are the most likely hazards with any thunderstorms. Peak
rainfall rates will be around a quarter of an inch per hour or
less, although rates up to 0.5 inches per hour many occur in any
thunderstorms or along the frontal boundary. Minor flooding is
possible if these rates occur, especially in low lying urban
areas or near recent burn scars.

As for winds, gusty south to southwest winds are expected ahead of
and near the front, generally 20 to 40 mph. Stronger SW winds
will affect the Antelope Valley and San Gabriel Mountains from
around 10 AM today through this evening. After this time, winds
will shift to the west to northwest and remain gusty into
Thursday. These winds will be strongest over the mountains and
interior, but may affect some coastal sections at times.

.LONG TERM (FRI-MON)...20/1222 PM.

Near normal temperatures are expected Friday when most highs will
be in the low to mid 70s. Then temperatures will fall to several
degrees below normal over the weekend, with highs in the 60s
common. There is a 30-50 percent chance of mainly light rain
focused across the foothills to interior sometime this weekend
thanks to moist upslope flow over the mountains and limited
instability. The storm energy is coming from the southwest to west
and is weak so significant wind concerns are unlikely, but it does
lend itself to below normal forecast confidence.

An active pattern (for April) may continue into early next week
as another weak storm is possible.

&&

.AVIATION...21/0919Z.

At 07Z at KLAX, the marine layer was 1500 ft with a weak inversion
up to 2100 ft with a maximum temperature of 13 C.

Moderate to low confidence from north to the south as the the
front approaches. Timing of rain and flight category changes could
be +/- 3 hours of current forecasts. There will be a 10-15%
chance of thunderstorms through 20Z Tue at KPRB, KSBP, and KSMX.

KLAX...High confidence in return of CIG/VSBY restrictions, but
timing of flight category changes could be +/- 3 hours of current
forecasts. Timing of light rain could also be +/- 3 hours of
current forecast. There is a 30% chance for an easterly wind
component of around 5-6 kt from 13Z to 18Z.

KBUR...High confidence in return of CIG/VSBY restrictions, but
timing of flight category changes could be +/- 3 hours of current
forecasts.

&&

.MARINE...21/211 AM.

For the Outer Waters, moderate to high confidence in current
forecast. Ahead of the front, there is potential for short-lived
SCA level winds through this morning, with best chances from the
Channel Islands northward. Seas will be near 10 feet through today.
For Wednesday through Friday, high confidence in combination of
SCA level northwesterly winds and seas with a 20-30% chance of
GALE force winds south of Point Conception Wednesday night. For
Saturday, high confidence in winds and seas remaining below SCA
levels.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Ahead of the front, there is
potential for short-lived SCA level winds through this morning,
with best chances from the Channel Islands northward. Seas will be
near 10 feet through today. For Wednesday through Friday, there
is a 60-80% chance of SCA level northwesterly winds, mainly in the
afternoon and evening hours. On Saturday, high confidence in
winds and seas remaining below SCA levels.

For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. This morning, winds and seas
should mostly remain below SCA levels, but localized gusts near
the front may briefly reach SCA levels. On Wednesday, high
confidence in SCA level northwesterly across all the southern
Inner Waters with a 20% chance of GALE force winds. For Thursday
through Friday, winds and seas are expected to remain below SCA
levels for most areas. The only exception will be the western half
of the Santa Barbara Channel with a 60-80% chance of SCA level
winds. On Saturday, high confidence in winds and seas remaining
below SCA levels for all of the southern Inner Waters.

A cold front will sweep across the coastal waters through today.
With this frontal passage, there will be a 20% chance of
thunderstorms across the coastal waters north of Point Conception.
Any thunderstorms that develop may produce brief heavy rain,
gusty winds and locally rough seas.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 10 AM this morning to 10 PM PDT
      this evening for zones 378>383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 6 PM PDT this evening
      for zones 645-670. (See LAXMWWLOX).

&&

$$

PUBLIC...Ciliberti/Schoenfeld
AVIATION...Schoenfeld
MARINE...Phillips/RAT
SYNOPSIS...MW/RS/CC

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office