Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 250040
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
440 PM PST Fri Nov 24 2017

.SYNOPSIS...
Above normal temperatures are forecast into Saturday. A low will
arrive Sunday for possible precipitation from Santa Barbara and
northward, then the possibility of precipitation should spread to
Los Angeles by Sunday night, and into Monday. A high should build
in next week for partly cloudy skies, offshore winds, and above
normals Tuesday into Friday.

&&

.SHORT TERM...(TDY-MON)

Unseasonably warm and clear conditions will continue through
Saturday. An upper ridge will weaken over the area, with highs
dropping between 3 to 10 degrees on average by Saturday afternoon,
but temperatures will still be above normal as weak offshore flow
continues. Mostly sunny skies are expected across the area,
although a few high clouds may stream overhead at times.

Saturday night into Sunday, a Gulf of Alaska low is forecast to
move into the Pacific Northwest. A shortwave trough will move
around the low and swing toward Central California Saturday night.
An initial band of rain will move onshore along northwest San
Luis Obispo County Sunday afternoon and evening, spreading south
along the Central Coast and inland over San Luis and Santa Barbara
Counties overnight. Precip chances were raised to likely across
the area for this period. Another batch of rain will move onshore
over the Central Coast late Sunday night into Monday, as the
shortwave overhead forms a cutoff circulation. This second impulse
is likely to continue rainfall over northern sections, also
spreading light rain further southeast over Ventura County and Los
Angeles Counties. At this time, rain totals through Monday will
be one quarter to one half inch for Santa Barbara and San Luis
Obispo Counties, with close to an inch near Rocky Butte, up to one
tenth in the Ventura Mountains, and less for the remainder of
Ventura and L.A. Counties.

South to Southwest winds will increase over the area Sunday
afternoon and night as the frontal system approaches. Gusty
southwest to west winds Monday morning will shift to the northwest
Monday afternoon, then increase to near-advisory level Monday
night from the north to northwest.

Marine layer low clouds were retained in the forecast for the
coast and Coastal Waters south of Point Conception Sunday morning,
although this is lower confidence. More certain will be mid to
upper level clouds increasing over the area from the northwest
Sunday through Sunday night, then decreasing from the northwest on
Monday. Temperatures will steadily decrease through the period,
with highs in the 60`s to near 70 by Monday.

.LONG TERM...(TUE-FRI)

The trough is expected to shift east of the area Monday night,
with an upper shortwave ridge developing by Tuesday morning. As
this occurs, winds will increase from the northwest to north
Monday night, shifting to north to northeast early Tuesday. These
gusty winds will likely be near advisory-level, especially over
the mountains and deserts, and they are likely to persist through
Thursday night. Models continue to depict Thursday morning as the
strongest offshore winds of the event.

The offshore flow will bring warmer temperatures to the area
again, although nothing like the heat of Thanksgiving week. Highs
are likely to remain in the upper 60`s to lower 70`s near the
coast, and in the mid-70`s in the valleys each day Tuesday
through Friday.

&&

.AVIATION...

25/0000Z

At 2345Z at KLAX, there was no marine layer. There was a sfc based
inversion with a hgt of 2200 feet and a temperature of 26 degrees
C.

Very good confidence in inland TAFs. All of the coastal TAF sites
have a 30 percent chc of MVFR vis 11Z-17Z and a 10 percent chc of
LIFR cigs and vis 12Z-16Z.

KLAX...Good confidence in TAF with a 30 percent chc of MVFR vis
11Z-17Z and a 10 percent chc of LIFR cigs and vis 12Z-16Z.

KBUR...Very high confidence in TAF.

&&

.MARINE...

24/200 PM

For the Outer Coastal Waters, moderate to high confidence in the
current forecast through Saturday. There is a 20-30 percent
chance of Small Craft Advisory conditions between Saturday night
and Sunday, increasing to 60-70 percent by Monday morning. There
is a 30-40 percent chance of gales on Monday and Monday night.
Winds will likely linger into Tuesday, then turn offshore for the
middle portion of next week.

For the nearshore waters, generally light winds are expected
through the weekend. There is a 40 percent chance of Small Craft
Advisory winds with choppy seas tonight and into Saturday for the
northern nearshore waters to the Central Coast. By early Monday
morning, there is a 60-70 percent of Small Craft Advisory level
winds. There is a 30-40 percent chance of gales on Monday and
Monday night. Offshore winds will develop on Tuesday and possibly
linger into Thursday. Small Craft Advisories maybe needed at times
nearshore for the middle portion of next week.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PST Saturday for
      zones 670-673. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 PM PST this evening
      for zone 676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK...(MON-FRI)
Between Sunday and Monday night, a storm system moving into the
region from the Gulf of Alaska could bring rain, high- elevation
snow and gusty west to north winds. After the storm passes,
offshore flow will likely develop and there is the potential for
elevated to near critical fire weather conditions Tuesday through
Thursday for portions of Southwest California. High surf is
possible at Southern California beaches between Monday and
Tuesday, and again between Wednesday and Thursday.

&&

$$

PUBLIC...Smith
AVIATION...Rorke
MARINE...Hall
SYNOPSIS...STu

weather.gov/losangeles


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