463
FXUS66 KLOX 171129
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
329 AM PST Mon Nov 17 2025

.SYNOPSIS...17/327 AM.

A cooler storm system will spread rain from northwest to
southeast across the area late tonight through tonight, with
decreasing showers continuing into Tuesday. Wednesday will offer a
brief respite from the rain with warmer temperatures. Another
storms is slated to arrive next Thursday and linger into Friday.

&&

.SHORT TERM (TDY-WED)...17/327 AM.

Key Message:
Moderate, Advisory level flooding and wind impacts are likely
with the storm that will push through the region today and Tuesday
due largely to the extremely wet conditions we experienced ahead
of the storm. Protective actions for consideration include: 1)
Avoiding travel during the peak of the storm, which will likely be
this morning for San Luis Obispo and Santa Barbara Counties, and
more towards the afternoon/early evening for Ventura and Los
Angeles Counties 2) Have multiple ways to receive weather warnings
and messages from local officials.

Weather Details:
Moderate to embedded pockets of heavy rain will march south along
and ahead of a cold front through this evening. Along and behind
the front there is a 10-20 percent chance of thunderstorms through
Tuesday early evening. Peak rain rates of 0.25-0.50 inches per
hour will be common, with isolated rates of 0.80+ inches per hour
likely near thunderstorms and S-SW facing foothills/coastal
slopes(especially in the Santa Ynez mountains and western Ventura
mountains). Minor roadway/small stream flooding, additional
rockslides/mudslides, and shallow debris flows near recent burn
scars will be common due to this storm being on the heels of the
historic rainfall we received just a few days ago. There is a
20-30 percent chance of reaching debris flow thresholds (15, 30,
60 minute durations) in the recent burn scars.

The wet grounds will also bring an increased risk of downed trees
with strong winds associated with any stronger winds. We have
issued an impact based Wind Advisory for most mountains and
interior areas given the increased risk for wind impacts even if
onshore winds fall just shy of our technical criteria in some
areas. Convective showers and thunderstorms may increase this risk
outside of the Wind Advisory as well. There is also the potential
for isolated waterspouts along and ahead of the cold front.

A secondary peak of thunderstorm chances is Tuesday afternoon
focused across interior mountains into most of LA County given its
more conducive location with better moisture and instability on
the east side of the departing cold upper low. Any thunderstorms
that do form could be slow moving or even stationary, leading to
the potential for very isolated flooding concerns as well as
debris flows near recent burn scars, especially concerning the
unusually wet conditions with peak rates potentially 0.25-0.5 inch
per hour with very isolated 0.80+ inch per hour.

Snow levels are expected to be above 7000 feet during the onset
of this next storm, but are expected to lower to between 5000 and
6000 feet by Monday night, and around 4500 feet on Tuesday. Snow
accumulations of 1-3 inches will be possible for elevations above
6000 feet, with higher amounts above resort levels (above 8000
feet) likely. On Tuesday, there is a small chance of snow showers
reaching down to the Grapevine along I-5, but any accumulations
would likely be minimal.

Wednesday will continue to be cool with some breezy northerly
winds across the interior. If good radiational cooling conditions
(light winds and mostly clear skies set up) we could see our first
frost/freeze of the year for many interior areas with upper 30s
in play for colder/sheltered coastal valleys as well.

.LONG TERM (THU-SUN)...17/322 AM.

Below normal confidence in a Thursday/Friday system as even
slight changes in its track and speed will make a large difference
on how much if any rainfall we see. Although its very likely
this one will be less impactful overall than the early week storm.
However, there is a 10-20 percent chance of similar impacts for
Los Angeles and Ventura County given the early week storm will
probably be a bit weaker for these areas and the Thursday/Friday
system may target these counties. This will be another cold system
with snow levels potentially around 5000-6000 feet for a majority
of the storm with several inches of snow possible above this
level should the storm come in on the wet side.

Above normal confidence in dry conditions next weekend into the
following week with temperatures likely rebounding to at least
near normal after the prolonged period of cool and unsettled
weather.

&&

.AVIATION...17/0607Z.

At 06Z at KLAX, there was no marine layer. There was a deep moist
layer up to around 7000 feet.

Overall low to moderate confidence in the 06Z TAFs due to
reduced confidence in CIGs preceding an approaching cold front,
and in CIGs/VSBY during and after the frontal passage. The timing
of rain and flight category changes may be off by 3 hours.

KLAX...Low to moderate confidence in the 06Z TAF. Light showers
possible throughout the forecast period, but most likely from 20Z
Mon to 04Z Tue. 40-70% chance RA from 20Z to 00Z, with a 30%
chance of IFR or lower conds during this time. There is a 40
percent chance of east wind component reaching 10 to 12 kts
sometime 15Z to 21Z.

KBUR...Low to moderate confidence in the 00Z TAF. Light showers
possible throughout the forecast period, but most likely from 20Z
Mon to 00Z Tue. 40-70% chance RA from 20Z to 00Z along with a 30%
chance of IFR or lower conds during this time.

&&

.MARINE...17/308 AM.

For the waters from southwest through northwest of the Channel
outside the southern California bight and the nearshore waters
along the Central Coast, Small Craft Advisory (SCA) level winds
continue to develop across the area this morning. Seas will
continue to build to SCA levels through today. SCA conditions
will persist through late Tuesday night. Winds and seas will
likely fall below SCA levels for Wednesday and Thursday, then
there is a moderate to high (30-50 percent) chance of SCA
conditions developing on Friday.

Inside the southern California bight, winds and seas will likely
remain below Small Craft Advisory levels through at least mid-
morning, then there is a high-to-likely (50-70 percent) chance of
SCA winds developing by this afternoon and continuing through
late tonight. Short-period seas will likely grow to SCA levels by
this evening. Conditions will likely fall below SCA levels for
Wednesday and Thursday, then there is a moderate-to-high (30-50
percent) chance of SCA conditions developing on Friday.

There is a 10-20 percent chance of thunderstorms across the
coastal waters through tonight. Any thunderstorms that develop
will be capable of producing brief heavy rain, small hail,
dangerous cloud to surface lightning, gusty and erratic winds,
locally rough seas, and possible waterspouts.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect until noon PST today for zones
      38-342-344-345-351>353. (See LAXNPWLOX).
     High Surf Advisory in effect from 2 PM this afternoon to 10
      AM PST Tuesday for zones 340-346. (See LAXCFWLOX).
     Wind Advisory in effect from 8 AM this morning to 4 PM PST
      this afternoon for zones 376>378. (See LAXNPWLOX).
     Wind Advisory in effect from noon today to 9 PM PST this
      evening for zones 379>382. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 9 AM PST Tuesday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect from noon today to 2 AM PST
      Tuesday for zones 650-655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Wednesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Munroe/Gomberg
AVIATION...Munroe
MARINE...Hall
SYNOPSIS...Smith

weather.gov/losangeles

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