000
FXUS66 KLOX 080011
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
411 PM PST Wed Dec 7 2022

.SYNOPSIS...07/207 PM.

Dry conditions are expected through Thursday afternoon. A weak
weather system bring light showers to the Central Coast late
Thursday. Then a stronger system will bring periods of heavy
precipitation to all areas Saturday afternoon into Sunday
night. Temperatures will remain below normal through the period.

&&

.SHORT TERM (TDY-SAT)...07/153 PM.

A quiet couple of days of weather leading up to the next storm
this weekend. Daytime highs will continue to be 4-8 degrees below
normal and morning lows as well. A freeze warning has been issued
for the Ojai Valley where temperatures are expected to drop below
freezing for at least a couple hours tonight.

Thursday afternoon and evening there will be a weak trough passage
that will drop a quarter inch of rain or less north of Pt
Conception. The remainder of Friday will be much like the previous
couple days, cool but plenty of sunshine.

The fun begins Saturday as a cold upper level system drops out of
the Gulf of Alaska. EPS solutions have been very consistent with
the timing and strength, and if anything have been slowly
adjusting the rain amounts higher with each run. We`re just
starting to get into the window of the higher res models and the
18z NAM is showing a bullseye of almost 2" in a 6 hour period
Saturday evening along the Big Sur Coast. This would likely
translate into hourly rates around a half inch in the favored
upslope areas. Given that the models show a low level jet of
50-55kt pushing as far south as Pt Conception it stands to reason
that there will be similar rates down through the upslope parts
of SLO and Santa Barbara Counties and likely into Ventura and LA
Counties as well. We may see some slowing of the system as it
approaches so confidence in the timing is still low, but rain
should arrive into Ventura and LA Counties either late Saturday
evening or in the pre-dawn hours Sunday morning.

As is typical with these strong low level jet situations the snow
level will bump up a fair amount and will likely be around 7000`
for the heaviest part of this storm through Saturday night. Gusty
winds will accompany the storm as well.

.LONG TERM (SUN-WED)...07/201 PM.

The primary cold front will push through the area relatively
quickly, generating about 6 hours of moderate to locally heavy
rain, followed by several hours of showers that will continue
through most of Sunday and into Sunday night. The heaviest
activity will be Sunday morning as the front pushes through
Ventura and LA Counties. Rain amounts are still in the one half to
one inch range for coast/valleys and 1-3" for foothills and
mountains. If models continue to trend wetter, or if the system
slows down, those number will have to be increased.

As we move into Sunday night the primary concern will be rapidly
lowering snow levels and possibly some accumulating snow on
Interstate 5 over the Grapevine. Elsewhere, showers will be
tapering off as we transition to a moderate northwest flow
pattern. Then dry but cool weather through mid week.

&&

.AVIATION...08/0010Z.

At 0005Z at KLAX, there was no marine layer nor an inversion.

Good confidence TAFs xcp for KSBP (a 30 percent chc of IFR cigs
vis 10Z-16Z) and KSMX (a 30 percent chc of no restrictions)

KLAX...Good confidence in TAF. Good confidence in any easterly
wind component remaining below 5 kt.

KBUR...Good confidence in TAF.

&&

.MARINE...07/1253 PM.

No changes to the marine forecast for the afternoon issuance,
however model solutions show timing differences in the 3 to 5 day
period.

For the Outer Waters, low confidence in current forecast. Winds
will likely remain below Small Craft Advisory (SCA) levels through
Thursday morning. There is a 30% chance of SCA level winds south
of Point Conception Thursday afternoon through evening, and a 20%
chance over the northern waters Thursday night/Friday morning. Another
chance for SCA level winds comes Saturday as another system moves
through. The major challenge for Friday through the weekend will
be the timing of cold fronts.

For the Inner Waters north of Point Sal, high confidence in
current forecast. Winds and seas are likely to remain below SCA
levels through Friday.

For the Inner Waters south of Point Conception, moderate
confidence in current forecast. Winds and seas are likely to
remain below SCA levels through Friday, but there is a 30% chance
of SCA level wind gusts across the western portions Thursday
afternoon through early Friday morning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Freeze Warning in effect from 2 AM to 9 AM PST Thursday for
zone 357. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...MW
AVIATION...Rorke
MARINE...Sweet/Lund
SYNOPSIS...MW

weather.gov/losangeles

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