Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 130057
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
457 PM PST Mon Nov 12 2018

.SYNOPSIS...12/140 PM.

Moderate to locally strong Santa Ana winds will continue through
Tuesday. Lighter offshore winds are expected Wednesday and
Thursday. A switch to onshore and a return of the coastal marine
layer will be possible Friday into next weekend. A weather pattern
change is expected during Thanksgiving week with the
possibilities for rain.

&&

.SHORT TERM (TDY-THU)...12/148 PM.

Strong Santa Ana event continues today and Tuesday with decreasing
winds expected Wednesday. Models predicting stronger surface
gradients Tuesday but weaker upper support so winds will likely be
5-10 mph weaker but still quite gusty with widespread single
digit humidities. So overall expect a pretty similar day Tuesday
as today. There`s a chance that wind advisories may need to be
extended into Wednesday for some of the area currently covered
with an advisory or warning but will wait to see how things look
tomorrow before deciding on an extension. Ref Flag Warnings have
already been extended through Wednesday afternoon due to the
continued low humidities and enough wind to create critical fire
weather conditions.

Even Thursday there`s still enough offshore gradient and winds
aloft to generate locally gusty winds at the surface but
definitely below advisory levels by that point.

There will be small warm up the next few days with high pressure
aloft pushing out the remaining cool air from the previous trough.
Overnight temps will continue to be quite chilly in wind protected
locations such as interior SLO, the Antelope Valley, and in and
around Ojai.

.LONG TERM (FRI-MON)...12/157 PM.

Cooling to begin most areas Friday as a trough replaces the ridge
aloft and gradients turn weakly onshore. Much cooler air will move
in as well and drop daytime temps 5-10 degrees by the weekend.
Will likely see some marine layer stratus reforming as early as
Saturday morning but no later than Monday. Winds will be much
lighter during the period.

By Monday afternoon and night models showing an upper low
developing just west of the California coast with some moisture
with it. Very low confidence though as it`s bumping into a ridge
of high pressure stretching from the Pac NW southeast through AZ
so expect quite a few variations of this solution the next several
days. For now will just continue the cooling trend but keep the
forecast dry.

&&

.AVIATION...13/0056Z.

At 0030z at KLAX, there was no marine inversion.

Overall...High confidence in the TAFs. Areas of smoke across the
region may cause MVFR VSBYs at times, particularly from KOXR
through KLAX. Otherwise VFR conditions will prevail throughout
the forecast period.

KLAX... High confidence in the TAF. VFR conditions will prevail
throughout the forecast period. There is a 20% chance of MVFR
vsbys in smoke between 03Z and 14Z. There is a 20% chance of east
winds greater than eight knots 13/14z- 18z.

KBUR... High confidence in the TAF. VFR conditions will prevail
throughout the forecast period. There is a 30% chance of LLWS.

&&

.MARINE...12/143 PM.

For the outer waters...There will be local gusts to 25 knots
through Tuesday in the southern outer waters. Otherwise and
elsewhere, the winds will remain below SCA levels through
Thursday.

For the inner waters north of Point Conception... Conditions will
remain below SCA levels through Thursday.

For the inner waters south of Point Conception...Just updated the
Coastal Waters Forecast to increase winds over the inner waters
south of Point Conception to speeds just below Gale category.
There will be strong SCA level winds today, especially south of
Rincon Point and below passes and canyons. This includes the
waters out to Catalina Island where there may be hazardous swells
and gusty winds in and around Avalon Harbor. The SCA will likely
need to be extended through Tuesday.

&&

.FIRE WEATHER...12/338 PM.

Moderate to strong Santa Ana winds combined with single digit humidities
will continue to bring VERY CRITICAL fire weather conditions across much
of Los Angeles and Ventura counties through Tuesday. During this time,
northeast winds gusting between 40 and 60 mph will be common across
wind favored areas. By Tuesday night and Wednesday, the offshore winds
are expected to diminish but will still see gusts in the 25 to 40 mph
range. These expected offshore winds in combination with persistent
single digit humidities has resulted in the extension of the Red Flag
Warning through 5 pm Wednesday for Ventura County, the Los Angeles county
mountains, Santa Monica mountains, Santa Clarita Valley, and San Fernando
Valley. Winds are expected to be weaker across the Los Angeles coast and
San Gabriel Valley Tuesday night into Wednesday, so Red Flag Warnings will
remain in effect through 5 pm Tuesday for these areas at this
time. LAX-Daggett gradient peaked at -6.8 mb this morning, and is
expected to peak above -7 mb on Tuesday morning.  A light
offshore wind influence will maintain dry conditions across
interior sections Thursday into Friday, maintaining elevated fire
weather conditions.

Fire weather conditions through Santa Barbara and San Luis Obispo
Counties will be elevated through this period with plenty of dry air
along with pockets of gusty east winds expected.

If fire ignition occurs, conditions will be favorable for very rapid fire
spread and extreme fire behavior including long range spotting,
especially today into Tuesday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect until 5 PM PST Tuesday for zones
      40-41-44-45-88-547. (See LAXNPWLOX).
     High Wind Warning in effect until 5 PM PST Tuesday for zones
      46-53-54. (See LAXNPWLOX).
     Red Flag Warning in effect until 5 PM PST Wednesday for zones
      240-244>246-253-254-288-547. (See LAXRFWLOX).
     Red Flag Warning in effect until 5 PM PST Tuesday for zones
      241-548. (See LAXRFWLOX).
PZ...NONE.

&&

.HAZARD POTENTIAL OUTLOOK (THU-MON).

No significant hazards expected.

&&

$$

PUBLIC...MW
AVIATION...DB
MARINE...Sweet
FIRE...Gomberg
SYNOPSIS...B

weather.gov/losangeles


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