Hidden Hills, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

822
FXUS66 KLOX 221137
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
437 AM PDT Thu May 22 2025

.SYNOPSIS...22/436 AM.

Stronger onshore flow will bring a cooling trend through
Saturday. Temperatures will remain above normal today, but
temperatures will cool to normal by Saturday. Night through
morning low clouds and fog, returning to Southland coastal areas
today, will expand northward and inland the next couple of nights
and mornings. A deep marine layer depth will be in place over the
weekend with night through morning low clouds and fog extending
well into the valleys.

&&

.SHORT TERM (TDY-SAT)...22/436 AM.

An upper-level ridge of high pressure in place the last several
days is breaking down. Onshore flow is strengthening as southwest
flow aloft continues to increase this morning. An eddy circulation
across the southern California bight is pushing low clouds and
fog into southern Los Angeles County. Clouds starting to spill
over into the western portion of the San Gabriel Valley and are
also trying to work their way north into the Ventura County
coastal plain.

A cooling trend will get underway today as onshore flow is progged
to continue to strengthen through the day. While today and Friday
will likely still remain above normal for most areas, cooling
will turn more significant Friday and Saturday, bringing the
coastal areas back to normal on Friday. A deepening marine layer
combined with stronger onshore pressure gradients will lead to
more marine air being transported into the coastal and valleys
area. AMDAR soundings from KLAX indicate a 700 foot deep marine
layer depth, which agrees well with the latest NAM BUFR time
height sections. The marine layer depth should deepen to between
900 and 1200 feet deep on Friday morning, which should allow for
clouds to filter into the San Fernando Valley. The marine layer
should then deepen additionally to between 2000 and 2500 feet
deep by Saturday morning.

North of Point Conception, clouds will continue to remain patchy
for this morning, but there will likely be better coverage of the
night through morning low clouds and fog tonight and Friday, and
more solid coverage will occur on Friday night into Saturday. Low
clouds could return to the southern Salinas Valley as soon as
Friday morning, but the chances are higher for Friday night and
into Saturday morning.

KSBA-KSMX pressure gradients will tighten tonight and again Friday
night. NAM-WRF solutions indicate the gradient tightening to -3.9
mb at 06Z Friday, but climatological regimes in place this time of
year should permit the gradient to likely fall between -4 and -4.5
mb earlier this evening. With some ample low-level wind support,
a wind advisory was added for gusty Sundowner winds across the
southwestern portion of Santa Barbara County from late this
afternoon and tonight. High-resolution multi-model ensemble
members indicate a broader expanse of the winds on Friday night,
while EPS ensemble members trend wind gust means higher at KSBA.
Another wind advisory may be needed for the same area on Friday
night while expanding across the Santa Ynez Range slightly.

.LONG TERM (SUN-WED)...22/436 AM.

The marine layer depth could thin slightly and the low cloud
extent could retract some on Sunday. Cluster analysis reveals
weak ridging aloft to be favored, but southwest flow should
persist and keep onshore flow in place. If there were a day for
clouds to struggle to clear from the coast, it could be Sunday as
the marine inversion should tighten and inhibit mixing of marine
intrusion. Stay tuned as this could be the wrinkle in the
forecast.

By Monday, troughing aloft should reestablish and linger through
much of next week. While there is some uncertainty on how strong
the trough will be, cluster analysis favor troughing for much of
the work week. EPS ensemble members keep temperature means closer
to climatological averages and a persistent night through morning
low cloud field in place.

&&

.AVIATION...22/1134Z.

At 0757Z, the marine layer depth was around 700 feet deep at
KLAX. The top of the inversion was 2000 feet with a temperature
near 24 degrees Celsius.

High confidence in TAFs for KPRB, KPMD, and KWJF.

Low to moderate confidence in remaining TAFs. Low clouds this
morning will remain IFR to MVFR as the Catalina Eddy has lifted
cigs higher than anticipated. Cigs may go in and out of sites
this morning, but all sites should clear by 18Z-20Z. MVFR vsbys
may linger into the afternoon at coastal sites due to shallow
inversion. Timing of arrival of cigs tonight may be off +/- 3
hours. MVFR cigs are generally expected as the Catalina Eddy
reforms tonight and continues to lift cigs. There is a 40% chance
for IFR to MVFR conds at KBUR/KVNY late tonight. Periods of light
to moderate LLWS and turbulence are possible between 22Z and 06Z
at KSBA.

KLAX...Moderate confidence in TAF. There is a 40% chance for cigs
008-010 through 17Z. Clearing time may be as early as 16Z or as
late as 18Z. MVFR vsbys may continue through 20Z. Arrival time
tonight could be off +/- 3 hours, and there is a 20% chance for
cigs 007-010. There is a 15% chance for an east wind component
reaching 8 kts after 07Z Friday.

KBUR...Low confidence in TAF. There is a 40% chance for cigs
007-015 and or vsbys 2-5SM after 07Z.

&&

.MARINE...22/215 AM.

High confidence in Small Craft Advisory (SCA) level winds and
seas continuing through Memorial Day Weekend in the Outer Waters,
with a 40-70% chance for GALES through late Friday night. Chances
for Gales decrease to 10-20% Saturday through Monday.

For the northern Inner Waters, high confidence in a combination
of SCA winds and/or seas through Friday, with highest chances in
the afternoon and evenings. There is a 60% chance for Gale force
winds this afternoon and evening, and a 40% chance Friday. There
is a 40-50% chance for SCA winds at times over the weekend.

There is a 60% chance for SCA level winds in the western portion
of the Santa Barbara Channel this afternoon through late tonight.
SCA level winds will be more widespread Friday, including
reaching the Ventura County coastline, and there is a 30% chance
for Gale Force winds in the western portion of the channel. There
is a moderate chance for SCA level winds across the western
portion of the channel each afternoon and evening over the
remainder of Memorial Day Weekend.

For the Inner Waters off the Los Angeles and Orange County coasts,
high confidence in conditions remaining below advisory levels
today. There is a 20-40% chance for local gusts to 25 kt to occur
Friday through Monday in the afternoons near Malibu and in the
western portion of the zone. Highest chances are Friday and
Sunday.

Dense fog with reduced visibility is possible at times through
this evening.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 3 PM this afternoon to 3 AM PDT
      Friday for zones 349-351. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zones 645-673-676. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM this afternoon to 9 PM PDT
      this evening for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect from 5 PM this afternoon to 3
      AM PDT Friday for zone 650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Friday for zone 670. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM this afternoon to 3 AM PDT
      Saturday for zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall
AVIATION...Lewis
MARINE...Lewis
SYNOPSIS...Hall

weather.gov/losangeles

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