897
FXUS66 KLOX 230046
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
546 PM PDT Thu May 22 2025

.SYNOPSIS...22/121 PM.

Stronger onshore flow will bring a cooling trend through
Saturday. Night through morning low clouds and fog, returning to
Southland coastal areas today, will expand northward and inland
the next couple of nights and mornings. A deep marine layer depth
will be in place over the weekend with night through morning low
clouds and fog extending well into the valleys.

&&

.SHORT TERM (TDY-SUN)...22/135 PM.

A weak trough approaching the west coast has initiated a cooling
trend that will continue at least through Saturday. The marine
layer has already begun to lift and low clouds will fill in across
the coastal valleys overnight. By Saturday highs will be back
below normal area-wide with a marine layer depth expected to be
near 2500 feet. The only coastal area potentially exempt from the
marine layer return may be southwest Santa Barbara County where
moderate northwest flow from the Central Coast and funneling
through the Santa Ynez range will persist, strongest in the late
afternoon and evening.

There is still some potential for minor warming Sunday as models
continue to show a quick little pop up ridge over the area.
However, onshore gradients are expected to reach almost 10mb
Sunday so any warmup will most likely be confined to the interior
with increasing southwest winds, especially across the Antelope
Valley.

.LONG TERM (MON-THU)...22/150 PM.

No real significant weather impacts next week. Temperatures are
expected to flat-line most of the week with highs +/- 3 degrees
of normal. The upper pattern is somewhat nebulous with a weak
upper low expected to undercut a developing ridge across the Pac
NW. Heights actually rise slightly through the period but onshore
flow remains quite strong most of the week so the most likely
outcome is a steady stream of night and morning low clouds and fog
for coastal and at least some valleys. Both deterministic models
linger the upper lows in the vicinity of southern California all
the way through the following weekend which could keep
temperatures on the mild side. However, there are a number of
solutions that push the low either north or retrograde it out over
the ocean with a much warmer air mass moving in from the east. So
needless to say a very low confidence forecast in the longer
range but with at least a possibility of a significant warming
trend going into June.

&&

.AVIATION...23/0022Z.

At 2353Z, the marine layer at KLAX was around 1000 feet deep. The
top of the inversion was at 2800 feet with a temperature of 22 C.

High confidence in TAFs for KPRB, KPMD, and KWJF.

Low to moderate confidence in remaining TAFs. The lowest
confidence is for the KSBP and KSBA, with a 20-30% chance of IFR
conds at KSBP overnight, and a 30% chance of no CIGs at KSBA. For
the Ventura and LA Coast/valley sites, the timing may be off by at
least +/- 2 hours, and flight categories may be off by 1 or 2.

KLAX...Moderate confidence in the 00Z TAF. Arrival and departure
of cigs may be off by +/- 2 hours. There is a 30% chance of MVFR
conds overnight instead of IFR. There is a 20% chance for an east
wind component reaching 7-8 kts from 07Z to 14Z Fri.

KBUR...Low confidence in the 00Z TAF. There is a 40% chance of no
restrictions overnight, and a 30% chance of MVFR conds instead of
IFR.

&&

.MARINE...22/118 PM.

For the Outer Waters, high confidence in Small Craft Advisory
(SCA) level winds and seas (at times) through Memorial Day
weekend. GALE force wind gusts are expected to become widespread
this afternoon through the late night hours. On Friday, GALES are
expected to become more "localized" centered around Point
Conception and the Northern Channel Islands (PZZ673/676). Also,
there is a 30% chance of GALE force gusts across NE portions of
PZZ670 Friday evening. Thereafter, minimal chances for GALES and
seas are expected to remain below SCA thresholds.

For the northern Inner Waters, SCA winds with GALE force gusts are
expected to develop this afternoon persisting into the overnight
hours - Seas will be near SCA levels during this time. Thereafter,
SCA winds will persist, with another chance (40%) for GALE force
gusts Fri afternoon/eve. For Memorial Day weekend, SCA winds are
likely especially during the afternoon/eve hours.

For the southern Inner Waters, SCA winds are expected to develop
late this afternoon across western portions of the Santa Barbara
Channel persisting through late tonight. On Friday, winds will be
more widespread reaching eastern portions including the Ventura
County coastline - 15% chc of GALE force wind gusts. There is a
moderate chance for SCA level winds across the western portion of
the channel each afternoon and evening over the remainder of
Memorial Day Weekend.

For the Inner Waters off the Los Angeles and Orange County coasts,
high confidence in conditions remaining below advisory levels
today. There is a 20-40% chance for local gusts up to 25 kt to
occur Friday through Monday in the afternoons near Malibu and in
the far western portion of the zone - Highest chances are Friday.

&&

.BEACHES...22/118 PM.

A long period southwest swell will bring elevated surf conditions
and high risk for hazardous rip currents through Memorial Day
weekend. Considering the expected high beach attendance for the
holiday, ocean rescues will likely be many. If you plan on
swimming in the ocean this holiday, make sure to swim near a
occupied lifeguard tower.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect until 3 AM PDT Friday for
      zones 349-351. (See LAXNPWLOX).
PZ...Gale Warning in effect until 9 PM PDT this evening for zone
      645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Friday for zone
      650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Friday for zone 670. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Saturday for zones
      673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW
AVIATION...Ciliberti
MARINE...Black
BEACHES...Black
SYNOPSIS...Hall

weather.gov/losangeles

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