527
FXUS66 KLOX 171004
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
304 AM PDT Thu Jul 17 2025

.SYNOPSIS...16/115 PM.

There will be a slight chance of showers and thunderstorms
Thursday into Friday across eastern Los Angeles County.
Otherwise, night through morning low clouds and patchy fog will
continue for the coasts and most valleys through the weekend.
Below normal temperatures are expected into early next week,
though a slow warming trend will develop Thursday and Friday.

&&

.SHORT TERM (TDY-SAT)...17/1205 AM.

The marine layer is much lower (1200 ft vs 3000 ft) compared to
ydy and this along with weaker on shore flow will result in less
low cloud coverage than ydy. The offshore trends will also allow low
clouds to clear a little earlier than they have been. A little bit
of moisture will advect into LA county later this afternoon and
will create a slight chc of TSTM over the eastern San Gabriels.
Max temps will be very similar to Wednesday save for the Paso
Robles area which will see about 8 degrees of warming as the
cooler southerly winds stop and turn northward.

Later this evening and the monsoon moisture influx will accelerate
as an upper low to the south switches the upper level flow to the
SE tapping into a wetter portion of the atmosphere. There is not
that much instability but with CAPE values around 700J/km any
little ripple of PVA rotating around the low could trigger a
TSTM. Although steering flow is very light, chances for any
flooding rains is under 5% as most of the moisture will be above
10000 ft. While the Central Coast will see another round of low
clouds the low cloud fcst south of Pt Conception is less certain
as the monsoon push may disrupt it. For now will keep the low
clouds in the fcst but would not be surprised if there are less
clouds than fcst.

The TSTM threat will continue over the LA county mtns and Antelope
Vly (and to a much lesser degree the San Gabriel Vly) through the
day on Friday. Aside from the morning stratus skies will likely be
partly cloudy over LA and portions of VTA counties. Max temps will
not change much across LA/VTA county, but the SBA south coast will
see some weak north winds which will bring 2 to 5 degrees of
warming. The interiors of SLO and SBA counties will also warm a
few degrees.

The monsoon flow cuts off late Friday night and Saturday will have
quiet weather. Again the marine layer south of Pt Conception may
be disrupted, but still it is more likely than not. Rising hgts
will bring 2 to 3 degrees of warming to most areas. Still, max
temps will come in 2 to 4 locally 6 degrees blo normals.

.LONG TERM (SUN-WED)...17/1214 AM.

A very benign 4 days of weather in the xtnd period. Srn CA will be
under dry SW flow as it is sandwiched between high pressure over
the desert SW and broad troffing over the PAC NW. Mdt to strong
onshore flow will return and this will drive a persistent night
through morning low cloud pattern with slow clearing (and no
clearing at some west facing beaches). While there will be some
gusty afternoon winds in the mtn and Antelope Vly they will be
below advisory levels. Max temps will change little each day and
will be 3 to 6 locally 8 degrees below normal.

&&

.AVIATION...17/0549Z.

At 0505Z at KLAX, the marine layer was 1200 ft deep. The top of
the marine inversion was at 4000 feet with a temperature of 22 C.

High confidence in KPMD and KWJF.

Low confidence in TAFs for KBUR and KVNY with a 40 percent chc of
IFR cigs 11Z-17Z.

Moderate confidence in the remainder of the TAFs. cig arrival
times may be off by 2 hours and VFR transitions off by one hour.
Cig hgts may be off by +/- 300 ft.

KLAX...Moderate confidence in TAF. Cigs may arrival as late as
10Z. VFR transition could occur any time between 19Z and 21Z.
There is a 30 percent chc of BKN008 conds through 16Z. No
significant easterly wind component is expected.

KBUR...Low confidence in TAF through 17Z then high confidence.
There is a 40 percent chc of OVC005 conds 11Z-17Z.

&&

.MARINE...16/755 PM.

For the Outer Waters, moderate to high confidence in current
forecast. Tonight through Thursday, high confidence in winds and
seas remaining below Small Craft Advisory (SCA) levels. For Friday
through Monday, there is a 30-50% chance of SCA level winds,
especially across PZZ673/676.

For the Inner Waters, high confidence in current forecast. Tonight
through Monday, winds and seas are expected to remain below SCA
levels for all of the Inner Waters.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...Rorke
AVIATION...Rorke
MARINE...RAT/Ciliberti
SYNOPSIS...MW

weather.gov/losangeles

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