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000
FXUS66 KLOX 161842
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1142 AM 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-THU)...16/1142 AM.

***UPDATE***

Temperatures are up 5-10 degrees from this time yesterday under
clear skies and high heights. The morning fog near Paso Robles has
dissipated. Expecting a return of overnight low clouds and fog
this evening, and more extensive along the central coast. No
impactful changes from the previous short term discussion

***From Previous Discussion***

A week`s worth of uneventful weather is in store for Srn CA.

A week ridge will nose over the southern half of the state today
and hgts will rise about 580 dam. Sfc high pressure is building
into the north and this will generate some gusty winds through and
below the N/S oriented canyons. There is no upper level support so
do not expect any of the gusts to reach advisory levels. The
offshore flow will keep almost all of the low clouds away with the
only concentrated low clouds in the Paso Robles area, otherwise just
patchy low clouds across the Central Coast. Max temps will be
today`s most significant talking point. Max temps will rise 6 to
12 locally 15 degrees today the result of a combination of April
sunshine, offshore flow, and rising hgts. Most max temps will end
up 3 to 6 degrees above normal. The coasts will rise into the 70s
while there will be plenty of low to mid 80s in the vlys.

The offshore flow will relax tonight and the low cloud pattern
will start to reform. Low clouds will likely reform across the
Central Coast and the Salinas River vly.

The 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.

Wednesday night and Thursday the ridge will be pushed to the east
by a weak trof. The trof will bring a mass of mid and high level
clouds - enough to make the day a mostly cloudy one. The lift from
the low 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 above normal. Max temps
across the csts and vlys will end up in the mid 60s to the mid
70s.

.LONG TERM (FRI-MON)...16/322 AM.

GFS and EC along with their respective ensembles are in good
agreement for the extended period.

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 weak 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.

Temps on Fri are forecast to be a few degrees below normal for
the coast and vlys with above normal temps elsewhere. There should
be a warming trend Sat and Sun, with Sun being the warmest day
during the extended period. With the marine layer expected to
deepen by Mon, temps will cool back to several degrees below
normal for the coast and vlys but remain above normal for interior
areas. When all is said and done, however, most max temps will
come in within 2 degrees of Thursday`s values.

Weak ridging will build in over the weekend and 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 ridge weakens on Monday. The onshore flow will also increase.
Look for an increase in the morning low clouds and a 2 to 4
degree cooling trend across the entire area.

&&

.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...16/856 AM.

In the outer waters, Small Craft Advisory (SCA) level winds and
steep seas will continue thru late tonight, then SCA conds are not
expected Wed-Thu night. SCA level NW winds are expected Fri-Sat.

In the inner Waters N of Pt. Sal, SCA level NW winds are expected
this afternoon/evening. SCA conds are not expected late tonight-Thu
night. There is a 30% chance of SCA level NW winds Fri, then SCA
level winds are likely Sat.

In the Inner Waters S of Pt. Conception, there is a 40% chance of
SCA level W-NW winds in the western SBA Channel this evening, and
again Sat, with a 20% chance in NW portions of the southern inner
waters. Otherwise, SCA conds are not expected thru Sat.

&&

.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 from 3 PM this afternoon to 9
      PM PDT this evening for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

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

weather.gov/losangeles

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