Acton, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

437
FXUS66 KLOX 211736
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
936 AM PST Sat Dec 21 2024

.SYNOPSIS...21/923 AM.

A significant high-surf event with coastal flooding is expected
this weekend into the upcoming week, with the most dangerous
conditions expected from Monday into Tuesday. Areas of dense fog
near the coast will create low visibilities at times through
Monday. Aside from a small chance for light rain near the San
Luis Obispo County coast this weekend, it will be dry through
Monday. A stronger weather system could bring light rainfall to
more areas Tuesday and Tuesday night. Temperatures will range
from near normal near the coast, to well above normal for interior
areas.

&&

.SHORT TERM (TDY-MON)...21/934 AM.

...Significant high-surf event with coastal flooding this weekend
into the upcoming week...

Light gradients this morning combined with the low sun angle
and longer nights are creating a favorable environment for dense
fog formation near the coast. Dense fog continues across the LA
Basin this morning with visibilities down to a quarter mile of
less at times. This is a common time of year for this due to the
above reasons and we can expect this again the next couple nights
until there is better mixing in the lower levels. That should
come no later than Tuesday with the arrival of the next weather
system. In the meantime, expect some restricted visibilities at
times near the coast.

Otherwise, pretty low impact weather through early next week. The
tail end of a weak system will may bring some very light rain to
northwest SLO County later today into Sunday morning. Coast and
valley temperatures will warm slightly through Monday before
crashing again with the next system on Tuesday.

Please reference the High Surf Warning and High Surf Advisory, as
well as the Coastal Flood Advisory, regarding the significant
high-surf event.

.LONG TERM (TUE-FRI)...21/446 AM.

The strong shortwave trough is forecast to cross the area Tuesday
through Tuesday night. Moisture will be limited with this system,
though enhanced ascent will bring light precipitation chances to
many areas. Rainfall amounts could reach up to one-quarter to
one-half inch north of Pt. Conception, with amounts below one-
tenth inch farther south.

Also, the proximity of an upper jet core to the local area, and
offshore LAX-BFL gradients increasing to around 5 mb, may support
a brief period of wind headlines late Tuesday into Tuesday night
(40% chance) for northwest to north winds. Winds will weaken
thereafter, but will remain occasionally gusty from the northwest
to north through the remainder of the week.

The trough will also usher cooler conditions into the area, with
high temperatures cooling to the 60s in most places by Wednesday.
Only a slight warming trend is anticipated through late week as a
midlevel ridge builds over the area. Present indications are that
the building midlevel ridge will keep the storm track well north
of the area. Ascent peripheral to one passing system will bring a
slight chance for light rain well north of Pt. Conception late
Thursday into Friday, though no appreciable rainfall amounts are
expected. Otherwise, it will remain dry through at least the end
of the upcoming week.

&&

.AVIATION...21/1706Z.

At 1632Z at KLAX, the marine layer was 100 ft deep. The top of
the inversion was at 2700 ft with a temperature of 16 C.

High confidence in TAFs for KSBA, KBUR, KVNY, KWJF, and KPMD.

Moderate confidence in TAFs for KPRB, KSMX, KSBP, KOXR, and KCMA.
There is a 10-30% chance for LIFR conds at all sites after 06Z,
with KPRB and KSBP being the lowest, and highest at KSMX, KOXR,
and KCMA. At the latter sites, there is also a 20% chance for
VLIFR conds after 10Z.

Low confidence in TAFs for KLAX, KSMO, and KLGB. VLIFR to LIFR
conds should improve to at least MVFR by 19Z. Low confidence on
minimum flight cat and timing of cig arrivals. Flight cats may be
off by one cat (20-30% chance for VLIFR conds) and timing may be
off by +/- 3 hours.

KLAX...Low confidence in TAF. VLIFR to LIFR conds should persist
through 18Z-19Z then improve to MVFR. Low confidence in minimum
flight cat and timing of cig arrivals tonight. Arrival time may
be off +/- 3 hours, and there is a 20% chance for vsbys less than
1/2SM and cigs less then VV002 after 07Z. No significant east
wind component expected.

KBUR...High confidence in 18Z TAF.

&&

.MARINE...21/732 AM.

High confidence in large, long period west to northwest swells
arriving this evening, lasting through next week. Peak seas will
be at least 20 feet across the Outer Waters and northern Inner
Waters, highest off the Central Coast, and around 12 feet in the
Santa Barbara Channel Monday and Tuesday. Small Craft Advisory
(SCA) seas will likely (70-80% chance) continue most of the time
through the end of next week. These conditions pose a risk for
damaging breaking waves at Morro Bay and Ventura Harbor entrances.

There is a 60-70% chance of SCA level winds for the waters around
the Channel Islands beginning tomorrow morning and persisting
through at least late Monday. SCA winds will then become more
widespread across most of the waters by Christmas Eve (Tuesday)
and last through Friday morning. There is a 20% chance of Gale
Force wind gusts for the Outer Waters from around Point Conception
south to San Nicolas Island from Wednesday morning through
Thursday, possibly extending into the western portions of the
Inner Waters south of Point Concpetion.

&&

.BEACHES...21/742 AM.

A large and long period west to northwest swell will bring
dangerously high surf, especially to west and northwest facing
beaches, of 18 to 25 feet to the Central Coast and 12 to 18 feet
to Ventura County during peak periods Monday through Tuesday. LA
and Santa Barbara Counties will see 8 to 12 foot surf Monday and
Tuesday. Otherwise, from this afternoon through most of next week,
advisory level surf can be expected and minor to moderate coastal
flooding is possible. Please reference our SRF and CFW products
for more details.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect from 10 PM this evening to 4 AM
      PST Wednesday for zones 87-349-350-362-366. (See LAXCFWLOX).
     High Surf Advisory in effect until 1 AM PST Sunday for zones
      340-346-354. (See LAXCFWLOX).
     High Surf Warning in effect from 1 AM Sunday to noon PST
      Tuesday for zones 340-346-354. (See LAXCFWLOX).
     Coastal Flood Advisory in effect from 2 AM Sunday to 9 AM PST
      Tuesday for zones 340-346. (See LAXCFWLOX).
     Coastal Flood Advisory in effect from 9 PM Monday to 9 AM PST
      Tuesday for zone 354. (See LAXCFWLOX).
     Dense Fog Advisory now in effect until 10 AM PST this morning
      for zones 366-368. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 2
      AM PST Thursday for zones 645-670-673-676. (See LAXMWWLOX).
     Small Craft Advisory in effect from 10 PM this evening to 4
      AM PST Monday for zone 650. (See LAXMWWLOX).

&&

$$

PUBLIC...MW/Cohen
AVIATION...Lewis
MARINE...Lewis/Lund
BEACHES...Lewis
SYNOPSIS...MW/Cohen

weather.gov/losangeles

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