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000
FXUS66 KLOX 250508
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1008 PM PDT Wed Apr 24 2024

.SYNOPSIS...24/538 PM.

Strong onshore flow and a deep marine layer will keep temperatures
much cooler than normal across much of Southwest California
through Friday. Morning patchy fog and drizzle are expected
across portions of the coast, valleys, and foothills. Warmer
weather is expected by the weekend into early next week.

&&

.SHORT TERM (WED-SAT)...24/756 PM.

***UPDATE***

Still plenty of cloud coverage visible in the satellite imagery,
and expect the low clouds to extend well inland tomorrow morning
as a trough will lift the marine layer. Look for morning drizzle
in most of southeast LA County. The patch of clouds that contained
some lightning activity mentioned in the previous short term
discussion seems to be dissipating to our south and should not
affect the sky this evening over our area.

It is still looking good for advisory strength winds beginning
later Thursday evening in the western Santa Ynez Mountains,
northern I-5 corridor, and Antelope Valley. Winds will increase in
strength and coverage in Friday.

***From Previous Discussion***

A deep marine layer remains in place, however the inversion
remains weak so clouds are generally focused across the inland
valleys up against the south facing foothills as well as the
Central Coast. Confidence remains low with regard to the sky
coverage later tonight and Thursday as a trough approaches from
the southwest. Satellite imagery shows some baroclinicity to it
with even several lightning strikes near the low center earlier
today. Models indicate significant weakening of the system as it
continues it`s trek towards either northern Baja or southern San
Diego County so chances for any redevelopment are slim. Still, the
low and mid level lifting associated with the low could generate
some morning drizzle across southeast LA County. Many of the
ensemble solutions suggest this as well.

Following the trough passage Thursday afternoon, increasing west
to northwest winds are expected that will continue into Friday. In
fact Friday has some of strongest winds this week with speeds up
to 40 mph near and over the coast and up to 50 mph across the
mountains and Antelope Valley. Expect there will be a need for
wind advisories, possibly as early as late Thursday afternoon, but
certainly by Friday.

Later Friday into early Saturday there is a 10-15% chance of light
measurable rain across the interior mountains from far western LA
County to Santa Barbara County as an inside slider trough brings
some additional energy aloft as well a little bit of moisture.
Snow levels are at least 6000 feet so there`s no threat of snow
over the Grapevine, but there may be some light showers there and
along the border with Kern County to around the Carrizo Plain in
southeast SLO County. All that should end around sunrise Saturday
leaving behind sunny skies in all areas with slightly warmer
temperatures than Friday.

.LONG TERM (SUN-WED)...24/201 PM.

Sunday and Monday will be similarly nice days across the area with
minimal stratus and warming temperatures. Monday will likely be
the warmest day in this stretch with highs in the mid 80s in the
valleys and upper 60s and 70s near the coast.

The rest of the week will be cooler with increasing low clouds and
fog as well as onshore winds, particularly later in the week as
another cold upper low drops out of the Gulf of Alaska.

&&

.AVIATION...25/0207Z.

At 0030Z at KLAX, the marine layer was 1400 feet deep. The top of
the inversion was at 2300 feet with a temperature of 11 C.

High confidence in desert TAFs. Low to moderate confidence in
remaining TAFs. Cigs will generally be high MVFR to VFR, except
lower in some mountain/foothill areas. Much uncertainty of cig
arrivals and dissipation, but expecting most TAF sites to see cigs
at times from 12Z onward.

KLAX...Moderate confidence in TAF. There is a 20-30% chance of no
cigs or cigs a category high than forecast during the period. Cigs
appear likely after 10Z. No east wind component expected.

KBUR...Low to moderate confidence in TAF, due to uncertainty in
arrival of cigs. There is a 20-30% chance of no cigs or cigs a
category high than forecast during the period.

&&

.MARINE...24/1005 PM.

In the Outer Waters, current Small Craft Advisories (SCA) remain
on track for tonight. SCA conds are expected Thu morning thru
Sun. There is a 50-70% chance of gales starting Thu evening thru
Mon, with the highest chances for the southern zone (PZZ676).
Lower confidence in gales for the waters north of Point Sal on
Thursday afternoon/evening.

For the Inner Waters N of Pt. Sal, moderate to high confidence in
the forecast. SCA level winds are likely in the afternoon/evening
hours Thu-Sun. There is a 50% chance of gales Fri afternoon into
late Fri night, and a 40-60% chance of gales Saturday night.

In the Inner Waters S Pt Conception, moderate confidence. Current
Small Craft Advisories (SCA) remain on track for tonight,
especially in the Santa Barbara Channel where winds are
consistently gusting from 23-27 kts. SCA conds are likely in the
SBA Channel and the western portions south of Point Mugu during
the afternoon/eve hours Thursday. Strong SCA with possible gales
appear likely Friday and there is a 50-60% chance of gales
starting Fri morning into Sat. Lower confidence in winds over the
weekend, as winds could shift more northerly limiting the SCA
level and stronger winds to western portions of the Santa Barbara
Channel.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect from 9 AM Thursday to 3 PM PDT
      Friday for zones 645-670. (See LAXMWWLOX).
     Gale Watch in effect from Friday afternoon through late
      Friday night for zones 645-655-670. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Thursday for
      zones 650-655-676. (See LAXMWWLOX).
     Gale Watch in effect from Friday morning through Saturday
      morning for zones 650-673. (See LAXMWWLOX).
     Small Craft Advisory in effect from 9 AM Thursday to 9 AM PDT
      Friday for zone 673. (See LAXMWWLOX).
     Gale Watch in effect from Thursday evening through Saturday
      morning for zone 676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW/jld
AVIATION...Phillips/Schoenfeld
MARINE...Phillips/DB/Schoenfeld
SYNOPSIS...jld

weather.gov/losangeles

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