613
FXUS66 KLOX 302132
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
232 PM PDT Tue Apr 30 2024

.SYNOPSIS...30/149 PM.

Mostly clear skies and warmer temperatures will prevail across
the region through this week, although some night through morning
coastal low clouds and fog can be expected at times. Locally
breezy winds will continue over the mountains and deserts through
Wednesday, then turn NE over interior portions of Ventura and Los
Angeles Counties Wednesday night into Thursday. Cooler
temperatures are expected Friday through the weekend with a
slight of rain.

&&

.SHORT TERM (TDY-FRI)...30/202 PM.

Most coast/valley areas are running a little cooler than yesterday
as gradients continue to trend onshore. Expecting a similar trend
again Wednesday with slightly higher coverage of marine layer
stratus, mainly south of Pt Conception. There`s still some
lingering northerly flow across the interior but those gradients
are weakening and winds tonight should mostly be below advisory
levels.

The biggest adjustment to the forecast today was to cut back on
the offshore winds for Thursday as models (particularly the NAM)
have really reversed course on that. Onshore flow will be lighter
but any northeast winds should be confined to the interior and be
well below advisory levels. High temperatures will only go up a
few degrees at most for Thursday, mainly mid 80s for the valleys
and low to mid 70s for coastal zones. Then turning cooler again
Friday as a trough approaches from the northwest and gradients
shift back to onshore again marine layer coverage expands.

.LONG TERM (SAT-TUE)...30/221 PM.

Still a lot of uncertainty this weekend with the approaching upper
low. The deterministic models are still split with the GFS
favoring an inside slider low dropping through interior California
while the EC keep the low mainly north of Lake Tahoe. The grand
ensemble mean solution is much closer to the farther north EC
solution and not surprisingly NBM pops are extremely low. This may
ultimately prove to be an accurate assessment of the rain chances
at this point there are still enough solutions with at least some
light rain or drizzle to have some mention of precip in the
forecast by later Saturday into Sunday. For what it`s worth all
the higher precip solutions from the earlier GEFS solutions were
gone on the 12z run and only 30-40% of the remaining solutions had
even light rain, perhaps indicating models are starting to move
towards a drier scenario for the weekend.

In any case, rain chances are mostly confined to late Saturday
and early Sunday so the majority of the daytime periods are
expected to be dry. The cooling trend that will have begun Friday
will continue through the weekend with highs 4-8 degrees below
normal, coolest on Sunday.

There will be slightly warming Monday but most models maintain
cooler than normal temperatures well into next week.

&&

.AVIATION...30/1851Z.

At 1122Z at KLAX, the marine layer was 1800 ft deep with an
inversion top at 3500 ft and a maximum temperature of 16 C.

Moderate confidence in LA County coast and valley TAFs. Low
confidence on KSBA, KOXR, and KCMA, with a 20% chance of no cigs
developing, and a 20% chance cigs a category lower than
forecasted. High confidence in all other TAFs. Timing of cig
arrival/clearing may be off by +/- 2 hours, with a 20% chance of
cig developing once category lower than forecast at times.

KLAX...Moderate confidence in TAF. Timing of cig arrival/clearing
may be off by +/- 2 hours, with a 20% chance of a couple hours of
cigs lowering to BKN008. There is a 20% chance of an east wind
component reaching 6-8 kts from 08Z-16Z Wed.

KBUR...Moderate confidence in TAF. Timing of cig arrival/clearing
may be off by +/- 2 hours, with a 20% chance of a couple hours of
cigs lowering to BKN008.

&&

.MARINE...30/929 AM.

For the outer waters, current Gale Warnings are on track with
gusty NW gales expected to continue until late tonight. Swell
will continue to be steep and choppy. After gales subside, Small
Craft Advisory (SCA) conds are expected for the outer waters,
Wednesday through Sunday. However, there is a 30% chance of gales
persisting into Wednesday night and resurfacing again Thursday
afternoon and evening.

For the inner waters N of Pt. Sal, SCA level winds are likely
through tonight. Then, there is a 60% chance of SCA winds during
the afternoon and evening hours Wednesday through Friday. Seas
are expected to be above SCA level through Wednesday.

For the Santa Barbara Channel, SCA level W-NW winds are expected
across the western portion during the afternoon through late
night hours today and Wednesday. Then, there is a 20-30% chance
of SCA winds each afternoon/evening Thursday and Friday across the
extreme western portion. Winds will likely remain below SCA
levels for eastern portions of the channel through Friday night.
Saturday afternoon through Sunday, there is a 30-40% chance of
widespread W to NW SCA level winds across the entire inner waters.

For the southern inner waters, there is a 20% chance of SCA level
W to NW winds across northwestern portions, near Anacapa Island
during the late afternoon through late evening hours through
Wednesday. Otherwise, good confidence in conds remaining below SCA
levels through Friday night. Saturday afternoon through Sunday,
there is a 30-40% chance of widespread W to NW SCA level winds
across the entire inner waters.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 2 PM PDT Wednesday for
      zones 340-346-354. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Thursday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zone 650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Wednesday for zones
      670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW
AVIATION...Schoenfeld
MARINE...Lund/Schoenfeld
SYNOPSIS...MW/Sirard

weather.gov/losangeles

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