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000
FXUS66 KLOX 162125
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
225 PM PDT Tue Apr 16 2024

.SYNOPSIS...16/212 AM.

Dry and warmer conditions will prevail across the region this
week and through the weekend. Low clouds and fog should also
affect portions of the coast and valleys during the night and
morning hours through the period.

&&

.SHORT TERM (TDY-FRI)...16/225 PM.

Synoptically, the area is under an EastPac ridge pushing 580 dam
(ish) heights over the area while most of the CONUS is in a deep
trough around a low near Minnesota. In the next 24 hours the
pattern over us will become zonal and then develop into a slight
trough. By Saturday the ridge should return, although weaker than
it is today. By midweek a trough begins to drop down the Pacific
coast associated with a Gulf of Alaska low that may actually bring
a little more rain to the area mid week.

Max temps rose 6 to 12 to locally 15 degrees today as the result
of a combination of April sunshine, offshore flow, and rising
hgts. The offshore flow will relax tonight and the low cloud
pattern will likely reform across the Central Coast and the
Salinas River vly. Low clouds are also probably going to be over
the Oxnard plain.

Skies will be sunny on Wednesday save for the low clouds which
will not last past mid morning. The offshore will be weaker and
this will allow for an earlier seabreeze which will bring 2 to 4
degrees of cooling to the csts/vlys. Hgts will rise another 2 or 3
dam as the ridge peaks and this will lead to another 3 to 6
degrees of warming across the mtns and far interior.

On Thursday the ridge will move to the east and a weak trof cover
the area, bringing enough mid and high level clouds to make the
day a mostly cloudy one. The lifting heights along with a sharp
increase in onshore flow to the east will bring low clouds to the
coasts and most of the vlys. The afternoon onshore push to the
east is fcst to be near 7 mb and its likely that the low clouds
will not clear many coastal areas. Look for 4 to 8 degrees of
cooling across the board - this will bring the csts and vlys max
temps down below normals. The mtns and the far interior, however,
will remain likely above normal. Max temps across the csts and
vlys will end up in the mid 60s to the mid 70s.

Weak troffing will persist over the area on Friday. There will be
another round of morning low clouds across the coasts and most of
the vlys. There will be weaker onshore flow in the afternoon and
this will allow for better clearing. The mid and high clouds will
also be past the area so there will be much more sunshine. The
lower hgts will serve to cool the area but the sunnier skies and
weaker onshore flow will counteract this cooling. The end result
is that there will be hodge-podge of warming and cooling across
the forecast area.

.LONG TERM (SAT-TUE)...16/224 PM.

Model solutions are in good agreement in the long term.  There
should be a warming trend Sat and Sun as the ridge reestablishes
itself. The onshore flow will relax even becoming offshore from
the north on Sunday. The amount of morning low clouds will subside
and Sunday may well end up cloud free. Max temps will rise 2 to 4
degrees each day. By Sunday cst/vly max temps will end up 2 to 4
degrees above normal while the mtns and far interior will be 5 to
10 degree warmer than normal. Almost all of the vlys will see
temps in the 80s.

The marine layer is expected to deepen by Mon as the ridge weakens,
and onshore flow increases, cooling temps to several degrees
below normal for the coast and vlys while the interior will remain
above normal. Most max temps will come in within 2 degrees of
Thursday`s values.

Some ensemble solutions have a 20% chance of 0.1" of rain on
Tuesday as the trough deepens, but there isn`t enough of a signal
for the NBM to catch on to it yet. There is a better, but still
small, chance for rain (only about 0.1") later in the week as the
10-day outlooks indicate a trough will drop down the coast from a
Gulf of Alaska low.

&&

.AVIATION...16/1829Z.

At 17Z, there was a weak marine inversion at KLAX at about 1500 ft
deep. The top of the inversion was at 2800 ft with a temp of 16
deg C.

Generally hi confidence in the 18Z TAFs for most airfields with
VFR conds expected thru the fcst period.

However, for KPRB there is moderate confidence low clouds and
LIFR conds will develop there late tonight and persist until about
17Z Wed. For KLAX and KLGB, there is moderate confidence that
MVFR cigs will develop late tonight and lingering into Wed
morning. The timing of any low clouds may be off +/- an hour or
so.

KLAX...Moderate confidence in the 18Z TAF. There is a 40%-50%
chance of MVFR cigs about 12Z-16Z Wed. Otherwise VFR conds will
prevail. Any east wind component should remain less than 6 knots.

KBUR...High confidence in the 18Z TAF with VFR conds thru the pd.

&&

.MARINE...16/156 PM.

Generally high confidence in the current forecast.

In the outer waters, Small Craft Advisory (SCA) level winds and
steep seas will continue thru late tonight, then SCA conds are not
expected Wednesday through Friday. There is then a 40%-50% chance
of SCA conds Friday night through Sunday.

In the inner Waters N of Pt. Sal, SCA conds are not expected
through Sunday, except there is a 20%-30% chance of SCA wind gusts
at times especially evening hours Friday through Sunday.

In the Inner Waters S of Pt. Conception, there is a 30% chance of
SCA level W-NW winds in the western SBA Channel this evening.
Otherwise, SCA conds are not expected through Sunday.

&&

.BEACHES...16/528 AM.

A long-period southerly swell will push into the coastal waters
tonight thru Wed night, and may bring low end high surf conds to
S facing beaches. There is a 30% chance of high surf of 4-7 ft on
S facing beaches of L.A. County Wed/Wed night.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke/jld
AVIATION...Sirard
MARINE...Sirard
BEACHES...DB
SYNOPSIS...Sirard

weather.gov/losangeles

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