247
FXUS66 KLOX 171121
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
421 AM PDT Fri Oct 17 2025

Updated Aviation Section

.SYNOPSIS...17/251 AM.

Offshore flow will continue through the end of the week and keep
warmer and drier pattern in place. Breezy offshore winds will
continue this morning, especially through and below passes and
canyons. A cooling trend will develop for early half of next week
with a return of low clouds and fog to the coastal areas.

&&

.SHORT TERM (TDY-SUN)...17/250 AM.

Offshore flow will continue to establish over the area today as
a ridge of high pressure to the north builds over the region. With
exception to some low clouds over the interior portions of the
area, mostly clear skies prevail over the region. A few reports of
breezy and sub-advisory offshore winds are occurring currently
across the region, but winds are largely expected to remain below
advisory levels. With the latest model solutions indicating a few
spots approaching 30 knots, there is a chance that local gusts to
45 mph could develop this morning, but these areas are likely to
stay isolated across the higher terrain.

The real story will be the warmer temperatures developing today
and into Saturday. Compressional heating with the offshore flow
pattern will drive up temperatures to a few degrees above normal
across the coastal and valley areas. Meanwhile, the interior
portions of the area will remain on the cool side of normal.
Temperatures were warmed slightly for today across the coastal and
valley areas to account for the compressional heating factors.
Above normal daytime temperatures will remain above normal into
Saturday.

In wind-sheltered areas, clearer skies and dry conditions will
permit radiative cooling processes to be much more efficient
tonight and into Saturday morning. As a result, Saturday morning
could start out a little chillier in wind-sheltered locations,
such as the Ojai and Santa Ynez Valleys, and across the interior
portions of the area, such as the Antelope and Cuyama Valleys.

A cooling trend will start to take shape on Sunday as offshore
flow starts to break down and be replaced by an onshore flow
regime. A return of night through morning low clouds and fog could
return as soon as Sunday morning but more likely for Sunday night
and into Monday morning. With the marine layer depth returning in
a shallow layer, dense fog could become a hazard to start the
week for the coastal areas.

.LONG TERM (MON-THU)...17/252 AM.

Onshore flow will continue to establish through early next week as
a weak upper-level trough to the southwest of the region near 30N
and 125W will gradually lift out across the region through
Wednesday. While the deterministic solutions mostly keep the
region dry with this trough, about a fifth of the latest EPS
ensemble members have light precipitation developing over the area
between Tuesday and Wednesday. Despite the outlier nature of the
wetter solutions, it should be noted that troughs to the southwest
of the region are typically not modeled correctly. Due to the
data-sparse region, low pressure areas to the southwest of the
region are a problematic feature to model. It is not surprising
to see the AI solutions of the EPS to have even more members with
precipitation. Confidence is high in a deep marine layer with
cooler temperatures, but caution should used in the precipitation
forecast. For now, NBM values remain in the forecast, but this
wrinkle in the forecast will likely need some time to get ironed
out.

&&

.AVIATION...17/1120Z.

At 11Z, the marine layer was 500 ft deep. The top of the
inversion was at 1500 ft with a temperature of 22 Celsius.

There is a 70% chance for LIFR at KPRB developing by 14Z today.
Otherwise high confidence in VFR conditions.

NE winds will develop again today, slightly stronger and more
expansive than Thursday. 10-15 knots and/or LLWS possible at
KSBP,KOXR, KCMA, KBUR, and KVNY. Light but noticeable UDDF over
area mountains.

KLAX...High confidence in VFR through at least 06Z Saturday. East
winds possible 12-16Z but moderate confidence that winds will stay
under 8 knots. There is a 10% chance of LIFR FG after 10Z
Saturday.

KBUR....High confidence in VFR conditions through Saturday. NE
winds in the area, but unlikely to cause issues at the terminal.

&&

.MARINE...17/203 AM.

Fairly high confidence in NO Small Craft Advisory (SCA)
conditions through at least the weekend, except for a moderate
chance of brief and localized gusts near 25 knots this evening
from Point Conception to San Nicolas Island. Seas should be long
period dominant by Saturday. There is a moderate risk of patches
of dense fog over the coastal waters over the weekend.

&&

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

&&

$$

PUBLIC...Hall
AVIATION...Kittell
MARINE...Kittell
SYNOPSIS...Hall

weather.gov/losangeles

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