Westchester California Weather Forecast Discussion

637
FXUS66 KLOX 101016
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
316 AM PDT Fri Oct 10 2025
.SYNOPSIS...10/256 AM.
Today there is a slight chance of showers across eastern Los
Angeles County due to tropical moisture. Areas of gusty winds out
of the north will begin this afternoon and will peak Saturday and
Saturday night. Winds will become northeasterly Sunday morning,
resulting in drier conditions and clear skies. There is the
potential for a significant rain event Monday through Wednesday
this upcoming week.
&&
.SHORT TERM (TDY-SUN)...10/315 AM.
Current satellite observations show Los Angeles County within the
far periphery of mositure bands from Tropical Cyclone Priscilla.
The mositure will last through today for LA County, thus a slight
chance of showers and thunderstorms remains, focused over the
extreme eastern portion of LA County, mainly the eastern San
Gabriel Mountains. Even so, based on the minimal precipitation
thus far and the strong steering flow, risk of flash flooding is
minimal with only light rain if any expected. A few lighting
strikes and gusty winds will be possible with any convective
cells that develop.
A trough of low pressure will dig down into the region, bringing
areas of gusty north- northwest winds starting this afternoon and
peaking on Saturday and Saturday night. Winds will be the
strongest along the Central Coast, southern Santa Barbara County,
the Interstate 5 corridor, and the western Antelope Valley and
foothills, along with favored interior mountains. Wind Advisories
have be issued for these areas.
Late Saturday night into Sunday morning, as the trough travels to
the east, surface pressure gradients will become offshore from
both the N-S direction and E-W direction. This will drive weak-
to-moderate offshore north-northeasterly (Santa Ana) winds across
favored mountains, the Santa Clarita Valley, and the hills above
Santa Barbara City. Gusts will likely peak around 30 to 40 mph
across the higher terrain and favored foothills. Sunday conditions
will become noticeably drier with clear skies, and the brief
Santa Ana event will yield elevated fire weather.
Daytime highs today will slightly above normal south of Point
Conception, followed by a drop in temperatures as a result of the
passing trough. Most areas will see highs a few degrees below
normal this weekend, although the offshore flow will lead to
slightly above normal temperatures for some valley areas on
Sunday.
.LONG TERM (MON-THU)...09/201 PM.
The major story next week is the potential for a significant
storm system Monday night through Wednesday morning as an upper
low drops from Canada down the West Coast to California. Although
there exists a wide range of outcomes from minor impacts to major
impacts, most EC and GFS ensemble members agree upon at least some
rain across all four counties Monday night into Wednesday
morning, with Tuesday being the best chance. Depending on the
track of the low, outcomes could be anywhere from widespread light
rain to significant flash flooding and debris flows, with all
burn scars in play. There is also a chance for enhanced mountain
rain if southwest flow coming off the low comes to fruition, as
this enhances the orographic impacts (which could be more
impactful for burn scars). Advisory level winds are also possible
with the incoming system, but again, there is a wide range of
options. Temperatures will drop significantly and there is a low
chance for mountain snow at the highest peaks. The current
forecast has rain totals and chances somewhere in the middle of
these ranges, but this is an evolving situation so changes to the
forecast in the coming days are likely. Monitor to forecast for
most up to date information as this is a highly uncertain but
potentially highly impactful scenario.
Not expecting much in the way of marine layer clouds as onshore
flow will be fairly weak to the east if not slightly offshore and
considerably offshore from the north until Monday when the
aforementioned upper level low swings its way into California.
Onshore flow will become dominant quickly, but the low should
create enough lift to inhibit any chances of marine layer cloud
development through at least Tuesday night.
&&
.AVIATION...10/0640Z.
At 0526Z at KLAX, the marine layer was 700 ft deep. The top of
the inversion was around 3300 ft with a temperature of 23 C.
Low to moderate confidence in KPRB/KSBP/KSMX/KCMA/KOXR as timing
of flight category changes may be off by 2 hours, and there are
chances that no cigs form through the period at KSBP (10%), KCMA
(30%), and KOXR (20%).
Moderate confidence for LA County coasts and valleys, with a
15-25% chance of brief IFR- MVFR cigs forming through 18Z Fri. For
all LA county sites, there is a 10-15% chance of showers or
thunderstorms through 00Z Sat.
KLAX...Moderate confidence in TAF. There is a 25% chance of
BKN006-BKN012 CIGs 08Z-18Z Fri, and there is a 15% chance of
showers and thunderstorms through 00Z Sat. No significant easterly
wind component is expected outside of any potential thunderstorm
outflow winds.
KBUR...Moderate confidence in TAF. There is a 15% chance of
BKN006-BKN012 CIGs 08Z-18Z Fri, and there is a 10% chance of
showers and thunderstorms through 00Z Sat.
&&
.MARINE...10/301 AM.
For the waters outside the southern California bight from southwest
through northwest of the Channel Islands, including the nearshore
waters along the Central Coast, winds will increase through this
Saturday afternoon. Widespread Small Craft Advisory (SCA) level
conditions will be very likely to imminent (70-90 percent) by
tonight, and continuing through at least early Sunday morning.
There is a likely (60-70 percent) chance of GALES this afternoon
through Saturday evening, highest from the waters near Point
Conception south to San Nicolas Island. There could be some lulls
in the winds during late night and early morning hours, but seas
will likely remain at SCA levels through Sunday. There is a
moderate to high (30-50 percent) chance of widespread SCA
conditions lingering into early Monday morning. Due to the GALES
and hazardous seas, inexperienced boaters should seek or remain
in safe harbor.
Inside the southern California bight, conditions are expected to
remain below SCA levels through this morning, then there is a
high-to-likely (45-65 percent) chance of SCA conditions across the
bight, highest across the Santa Barbara Channel from this
afternoon through Sunday. Winds will be strongest across the
western portion, which has a moderate-to-high (30-50 percent) chance
of GALES Saturday afternoon and evening, but widespread SCA level
conditions have a high chance of developing on Saturday afternoon
and evening. Short-period hazardous seas could develop across the
Santa Barbara Channel on Saturday evening, with winds and seas
potentially reaching Ventura County harbors, such as Ventura and
Channel Islands Harbor during this time.
Moisture associated with rapidly weakening Tropical Cyclone
Priscilla off the Baja California coast will move north through
this evening. There is a slight (10-20 percent) chance of showers
and thunderstorms for the southern coastal waters, highest from
south of Dana Point into the San Pedro Channel adjacent to Los
Angeles and Orange Counties. Any thunderstorm that forms will be
capable of producing locally gale force winds and rough seas,
dangerous lightning, and heavy rainfall with reduced visibility,
and even a waterspout.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from noon Saturday to 10 AM PDT
      Sunday for zones 88-350-352-353-375>379-381-383. (See LAXNPWLOX).
     Wind Advisory in effect from noon Saturday to midnight PDT
      Saturday night for zones 340-341-346>348. (See LAXNPWLOX).
     Wind Advisory in effect from 5 PM this afternoon to 10 AM PDT
      Sunday for zones 349-351. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from 9 AM this morning to 3 PM
      PDT Saturday for zones 645-670. (See LAXMWWLOX).
     Gale Watch in effect from Saturday afternoon through late
      Saturday night for zones 645-670. (See LAXMWWLOX).
     Small Craft Advisory in effect from 3 PM this afternoon to 3
      AM PDT Sunday for zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zones 673-676. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM this afternoon to 3 AM PDT
      Sunday for zones 673-676. (See LAXMWWLOX).
&&
$$
PUBLIC...Schoenfeld/Lewis
AVIATION...Schoenfeld
MARINE...Hall
SYNOPSIS...Schoenfeld
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox

NWS LOX Office Area Forecast Discussion