237
FXUS66 KLOX 281800
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
1100 AM PDT Sun Apr 28 2024

.SYNOPSIS...28/906 AM.

Some coastal low clouds and fog will be possible each night and
morning through late this week, otherwise mostly clear skies with
warmer temperatures can be expected during the period. Gusty west
to north winds will prevail over the mountains and deserts at
least through Monday.

&&

.SHORT TERM (TDY-TUE)...28/905 AM.

***UPDATE***

There were some low clouds noted this morning over the Salinas
River Vly and the inland SBA Central Coast to the Santa Ynez Vly.
These low clouds will likely dissipate by late this morning.
Otherwise, mostly sunny skies covered the forecast area this
morning with little change expected thru the afternoon.

Gusty W to N winds to Advisory levels will affect portions of the
forecast area at times thru today, including the SW SBA County
mtns and coast, VTU County mtns, L.A. County mtns along the I-5
Corridor, and the western Antelope Vly foothills into the Antelope
Vly. A Wind Advisory is in effect for these areas, where winds
could gust to 45 to 50 mph especially this afternoon. Breezy to
gusty W-NW winds will also affect much of the coast and adjacent
vlys thru this afternoon, strongest on the Central Coast where
winds could approach Advisory levels at times.

Some upper level ridging will move into the forecast area today,
with H5 heights increasing to around 576 dam. This will help temps
to warm up a few more degrees over yesterday and be near normal
to a few degrees above normal for many areas away from the
immediate coast this afternoon. Highs for the inland coast to the
vlys and lower mtns should reach the 70s to around 80.

***From Previous Discussion***

Not much going on in the short term other than some winds and a
slow increase in the amount of night through morning low clouds.
The main storm track is well north of the area and NW slightly
cyclonic flow will be over the area today and Monday on Tuesday
the flow will turn a little more westerly and a little more
cyclonic. At the sfc a large high pressure system to the WNW of
the Bay Area will bring strong NW winds to the waters and the
Central Coast. A meso sfc high near Bakersfield will keep
northerly offshore flow going across eastern SBA county, VTA
county and western LA county.

Monday will be much like today just a little better low clouds
coverage. The winds will continue through the afternoon. There is
a decent chc (30-40 percent) that wind advisories will be need to
be extended into Tuesday. Another 1 to 2 degrees of warming will
bring max temps to normals or a degree above.

The offshore flow from the north increases to 6mb on Tuesday
morning. The canyon winds will likely extend down from the mtns
and into the vlys and then the csts as it passes through various
N/S passes and canyons. Short range high rez ensembles indicate
only a low chc (25 percent) of advisory level winds across VTA/LA
counties but a much higher chc (70 percent) across the western
half of southern SBA county.

.LONG TERM (WED-SAT)...28/310 AM.

The EC and GFS mean ensembles and deterministic are in generally
good agreement thru Thursday with broad pos tilt troffing on
Wednesday giving way to NW flow on Thursday. There will only be
minimal low clouds on Wednesday mostly across the LA county south
coast. Lower hgts and stronger onshore flow will bring 2 to 4
degrees of cooling to most areas. High pressure is fcst to move
into NV on Thursday morning and will set up offshore flow from
both the N and E. A low end Santa Ana wind event will develop.
There will be no low clouds and 3 to 6 degrees of warming.

There is not much mdl agreement either in the deterministic side
or ensemble side of things for the Friday and Saturday forecast.
fortunately the consequences will not be great the EC fcst will
be cooler with more marine layer clouds and the GFS fcst will
trend warmer with less marine layer clouds.

&&

.AVIATION...28/1758Z.

At 17Z at KLAX, the marine layer was 1700 ft deep. The top of the
very weak inversion was around 2700 ft with a temp of 13C.

High confidence forecast except coastal TAFs KSMX and south
including KLAX. There is a 50-70 percent chance of MVFR/IFR cigs
between roughly 08-18Z for KLAX/KLGB/KSMO, 30-50 percent chance
for KSMX/KOXR and a 10-20 percent chance for KSBA/KBUR.

Gusty NW-N winds expected for northern and interior TAFs may be
off by 5 kts at times.

KLAX...Moderate confidence in TAF. There is a 20% chance of
low MVFR to IFR cigs 13Z-17Z today. There is a 30% chance of
conds remaining VFR tonight. No east wind component expected.

KBUR...High confidence in TAF with VFR conds thru the pd.

&&

.MARINE...28/911 AM.

Small Craft Advisory (SCA) winds will very likely increase to gale
force late morning through early evening across the outer waters
today. A very long period of gale force winds is expected,
continuing thru at least Tue night. Winds will occasionally drop
below gale thresholds, but for the most part, gales are expected
across much of the outer waters much of the time. SCA conds are
expected Wed thru Thu, with a 30% chance of gales persisting into
Wed evening.

In the inner waters N of Pt. Sal, SCA level winds are likely thru
Tue night, especially in the afternoon/eve hours. There is a 50%
chance of SCA conds during the afternoon/eve hours Wed/Thu. Seas
are expected to be near SCA levels during the periods of weaker
winds. There is a 25% chance of gale force winds during the
afternoon/eve hours today thru Tue.

In the SBA Channel, SCA level W-NW winds are expected across
western portions during the afternoon thru late night hours today
thru Wed. There is a 50% chance of SCA conds across the eastern
portions late this afternoon and evening, and a 40% chance during
the afternoon and evening hours Mon thru Tue.

In the southern inner waters, there is a 40% chance of SCA level W
to NW winds across northwestern portions, mainly from Anacapa Island
to Malibu during the late afternoon thru late evening hours thru Tue.

Widespread strong to gale force winds will keep dangerous sea
conditions across much of the coastal waters (particularly the
outer waters) thru the middle of the week, with short-period,
steep, and choppy waves. There may be dangerous breaking waves
near west-facing harbors. Mariners should plan accordingly.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory now in effect until 3 PM PDT Monday for zones
      349-351. (See LAXNPWLOX).
     Wind Advisory remains in effect until 3 PM PDT Monday for
      zones 376>378-381-383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Monday for zone
      650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zone 670. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM this afternoon to 3 AM PDT
      Wednesday for zone 670. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Wednesday for zones
      673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke/Sirard
AVIATION...Munroe
MARINE...DB/RM
SYNOPSIS...Sirard

weather.gov/losangeles

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