975
FXUS66 KLOX 211137
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
337 AM PST Fri Nov 21 2025

.SYNOPSIS...20/1127 PM.

A storm will bring rain and mountain snow to the area through
Saturday morning, heaviest this morning across Los Angeles
County. Gusty east winds are expected today and Saturday morning
in some areas. High temperatures will rise to near normal by
Tuesday and Thanksgiving looks dry with above normal temperatures.

&&

.SHORT TERM (TDY-SUN)...21/252 AM.

A very interesting morning so far. A double-barrled low pressure
system (both sfc at aloft) is affecting the area. The low of
greatest consequence is almost directly over Catalina Island and
is hurling convective showers across the inner waters and southern
LA County (Orange County too). There is a large amount vorticity
in the area and this atmospheric twist has allowed and will allow
the shower that form to spawn waterspouts and possible weak
tornados. More importantly the lift from the PVA is helping the
shower to over produce some flooding (with rainfall rates
approaching an inch per hour) across the southern LA
County/Orange county area. The low and vort lobe are quite
compact and many areas of LA and VTA counties are dry. The peak of
the storm will be from now through about 700 am. The low will
weaken and the storminess will decrease through the rest of the
morning. A few showers may persist into the afternoon esp over the
mtns. Its likely that the LA coast, the San Gabriel Vly and the
San Gabriel Mtns will see a third to two thirds of an inch of
additional rainfall with local 1 inch amount possible under
heavier showers. Only a quarter inch is likely across western LA
county and VTA county will likely see a tenth or less. While it
not out of the question for a shower to form over SLO or SBA
counties, any showers that do form will be insignificant.

In the mtns snow will fall as low as 4000 feet with a dusting
possible at the top of the I-5 Grapevine. North winds wrapping
around the upper low will bring accumulating snow to north slopes
and hier peaks. Likely snow amounts will be 3 to 6 inches above
6000 ft and 1 to 3 inches for elevations between 5000 and 6000
feet.

There will be decreasing clouds in the afternoon. This along with
easterly downsloping winds created by the wrap around from the
departing low will bring 5 to 10 degrees of warming to most
coasts and vlys. The LA cst and vlys will see the clouds linger
the longest and will likely only see 2 to 5 degrees of warming.

Offshore flow will develop early Saturday morning. The N to S grad
will peak near 5 mb and the E to W grad will be near 4 mb. There
will also be some upper support from the departing upper low.
These two items should combine to bring advisory level wind gusts
35 to 45 mph to portions of western LA county and eastern VTA
county. SLO and SBA counties should start out mostly sunny but VTA
and LA county will be mostly cloudy in the morning with skies
turning sunny by afternoon. Hgts will not climb too much only
reaching 564 dam in the afternoon. Still the extra sunshine and
offshore flow will boost max temps 4 to 8 locally 10 degrees.
Despite this warming all max temps across the area will still be 2
to 4 degrees blo normal.

By Sunday the upper low will have moved into AZ and a weak ridge
will nose in from the west. There will 2 to 3 mb onshore trends
and any offshore winds will be much weaker than Saturday`s. Hgts
will rise to 576 dam and this will warm the mtns and far interior
by 3 to 6 degrees. The much weaker offshore flow will bring an
earlier and stronger sea breeze to the csts and vlys and max temps
there will cool 3 to 6 degrees.

.LONG TERM (MON-THU)...21/1222 AM.

Dry conditions are forecast through the xtnd period. At the upper
levels both the EC and GFS as well as the ensemble means all show
some sort of weak ridging over Srn CA xtndg from an upper high to
the SW of Pt Conception. Hgts will start out near 578 dam but will
rise to about 584 dam by Thanksgiving Day. At the sfc there will
be about 3 to 5 mb of offshore flow both from the N and S
strongest from the N. Somewhat oddly the pressure gradients are
forecast to exhibit little in the way of diurnal change.

The offshore flow will not have any upper or thermal support so
while there will be offshore breezes through the period it does
not look like they will reach advisory levels.

Blo normal max temps will continue on Monday with values mostly in
the mid 60s to lower 70s across the csts and vlys. Steady warming
will bring Thanksgivings max temps to above normal with temps
topping out in the upper 60s and 70s.

Some mdl solutions do show some rain developing 9 or 10 days from
now on the last weekend of the month. The EC-AI mdl that has been
performing best at these time frames is dry.

&&

.AVIATION...21/1134Z.

At 0815Z at KLAX, there was no marine layer. There was a deep
moist layer extending to over 6000 feet.

Low confidence in all TAFs through 21Z with frequent changes in
both cig and vis. Better confidence in VFR conds aft 21Z

KLAX...Low confidence in TAF through 21Z. Cig and Vis will vary
frequently with cigs possible anywhere from BKN008 to BKN040. Vis
will likely vary from 2SM To 6SM in RA and BR. Better confidence
in VFR cigs aft 21Z. Good confidence that there will be at least
a 8kt east wind component through at least 02Z with a 18kt east
wind component possible through 15Z.

KBUR...Low confidence in TAF through 21Z. Cig and Vis will vary
frequently with cigs possible anywhere from BKN008 to BKN040. Vis
will likely vary from 2SM To 6SM in RA and BR. Better confidence
in VFR cigs aft 21Z.

&&

.MARINE...21/242 AM.

Low confidence in forecast, especially regarding winds. It is
best to alter any plans and remain in safe harbor until conditions
improve this weekend.

A storm system is stalled inside the Southern California Bight. It
will bring periods of gusty winds, a large west-northwest swell
(especially for the Outer Waters), rain, and isolated
thunderstorms to the waters today. The best chance for
thunderstorm activity is this morning. Any thunderstorm can
produce erratic wind shifts, heavy rain, lightning, and even
waterspouts.

A combination of Small Craft Advisory (SCA) winds and seas will
affect most of the coastal waters through much of the weekend.
Look for seas of 10-12 feet across the Outer Waters, 10 feet for
the nearshore Central Coast Waters, and 4 to 6 feet inside the
Southern California Bight. Wind directions will vary considerably
through the course of the storm which will will result in rough,
confused seas, especially south of Point Conception.

NE winds will prevail through Saturday morning as nearly
stationary storm system spins inside the Southern California
Bight. Winds will be strongest from Ventura to Santa Monica (20-30
knots), but NE winds gusting up to 25 knots will occur nearshore
from Palos Verdes south through Orange County. NE winds may reach
the Channel Islands with much lower chances for Catalina Island.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Flood Watch remains in effect until 7 AM PST this morning for
      zones 88-362-366>373-379-380-548. (See LAXFFALOX).
     Wind Advisory in effect from 10 PM this evening to 10 AM PST
      Saturday for zones 88-354-355-362-369-371-374-375. (See LAXNPWLOX).
     High Surf Advisory in effect until 3 AM PST Monday for zones
      340-346-354. (See LAXCFWLOX).
     Winter Weather Advisory remains in effect until 10 AM PST
      this morning for zone 377. (See LAXWSWLOX).
     Winter Weather Advisory remains in effect until 4 PM PST this
      afternoon for zones 379-380. (See LAXWSWLOX).
PZ...Small Craft Advisory in effect until 3 AM PST Saturday for
      zones 650-655-670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke
AVIATION...Rorke
MARINE...Lewis/CC
SYNOPSIS...MW/RK

weather.gov/losangeles

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