Nipomo, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

039
FXUS66 KLOX 171609
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
809 AM PST Wed Dec 17 2025

.SYNOPSIS...16/726 PM.

Dense fog will affect the Los Angeles area tonight and Wednesday
morning. Well above normal temperatures will continue through
Friday, with locally gusty north to northeast winds peaking
tonight through Wednesday Night. Dry conditions will continue at
least through Saturday, but a storm will affect the area sometime
early to mid week next.

&&

.SHORT TERM (TDY-FRI)...17/745 AM.

***UPDATE***

We have added the San Gabriel to the Dense Fog advisory that
covers coastal areas south of roughly Santa Barbara, including
Downtown Los Angeles.

Winds are beginning to pick up in the mountains (Sandberg gusted
to 55 mph last hour) and even some foothill areas. So current Wind
Advisories look good with no changes anticipated.

The focus of today will be on the potential significant storm that
has trended towards targeting southwest California on the 24th and
25th with active weather possibly continuing beyond that time.

***From Previous Discussion***

The marine layer is currently 800 ft deep south of Pt Conception.
A weak eddy has brought low clouds as far north as Santa Barbara
and unexpectedly in the San Gabriel Vly as well as the eastern
portion of the San Fernando Vly. A dense fog advisory is in effect
until 10 am Wednesday for the coasts from KSBA and southward. The
low clouds will slowly burn off this morning. Skies, otherwise,
will be partly cloudy as some mid and high level clouds drift
overhead. Max temps across the csts will be similar to Tuesday`s
with the shallow marine layer preventing much warming (there is a
chc that the offshore winds will break through the marine layer
and produce warmer than fcst temps across the csts). Most of the
interior will be cooler as the northerly flow brings in cooler air
from the San Joaquin Vly.

Winds will the bigger story today. Moderate offshore flow from the
north and a little upper level support from the upper high will
likely bring advisory level winds to most of the mtns and vlys of
LA/VTA county as well as the Santa Ynez range, the Antelope Vly
and the Malibu coast. There is a chc that the winds will affect
the Santa Monica City and KLAX area as well. A little less
confidence in these wind advisories as KBFL- KLAX pressure
gradient may be a little unrepresentative due to the Tule Fog`s
effect on the KBFL pressure. The peak of the winds should come
late this afternoon and evening.

The E/W gradient becomes more offshore on Thursday and this will
tilt the winds to the NE and set up a weak Santa Ana event. It
does not look like it will produce advisory level wind gusts. It
will limit the low clouds and fog to the Long Beach area. The
offshore flow and lack of marine layer will allow max temps across
the csts to soar 8 to 12 degree. Weaker cool air advection will
bring some warming to the interior as well. The Central Coast will
be the only cooler spot as the offshore push there will be weaker
and will allow for an earlier sea breeze. Most max temps will end
up 10 to 15 degrees above normal.

On Friday the ridge will be pushed to the south and flat westerly
flow sets up over the area. Hgts will fall to about 585 dam (still
well above normal). Low clouds will be similar to Wednesday and
pretty much confined to the Long Beach area. Much weaker offshore
flow at the sfc will lead to 3 to 6 degrees of cooling across the
csts/vlys.

.LONG TERM (SAT-TUE)...17/236 AM.

Flat westerly flow will continue over the area on Saturday. Hgts
will dip to 582 dam. Onshore flow to the east and weaker offshore
flow from the north will allow for decent amount of coastal low
clouds. The southern edge of an atmospheric river (AR) affecting
the northern portion of the state may (20 percent chc) dip just
far enough to south to bring some light rain to SLO county. The
cooling trend will continue as falling hgts and better onshore
flow combine to lower most temps 3 to 6 degrees. The Central Coast
will be the exception with little change in temps. Max temps,
however, will remain above normal (well above normal across the
mtn and far interior).

The upper flow pattern changes to a more SW to NE direction on
Sunday as the AR system sags a little more to the south. A slight
chc or chc (20 to 30 percent) of rain will develop over SLO and
Western SBA counties. Other areas will just see increasing clouds.
Max temps will fall 2 to 3 degrees across almost all of the area.

The system is forecast to stall out on Monday. The 20-30 percent
chc of rain will remain over SLO and Western SBA counties.
Rainfall totals during this time will most likely be under a tenth
of an inch with perhaps the exception of the far NW tip of SLO
county which could see more. Max temps will change little from
Sunday`s values.

Things become a little more interesting on Tuesday as the AR sags
south and the flow becomes even more SW to NE. Rain chances will
overspread the entire area and now sit around 20 percent for LA
county, 30 percent for VTA county, 40 to 50 percent for SBA
county and 50 to 60 percent for SLO county. SLO county may see a
quarter inch of rain (three quarters of an inch over the extreme
NW tip) with a tenth of an inch elsewhere.

Deterministic, ensemble and AI mdls all are converging on the idea
of a large atmospheric river storm affecting the entire area
on the 24th and Christmas. There is the potential for this system
to be a big rain maker with all the attendant problems of such an
event. SoCal residents are urged to stay as informed as possible
about this developing situation.

This will not be much of a snowmaker at all with snow levels at or
even above the resort levels.

&&

.AVIATION...17/1010Z.

At 0845Z, the marine layer depth was around 900 feet deep at KLAX.
The top of the marine inversion was near 1800 feet with a
temperature around 21 degrees Celsius.

Through 20Z, high confidence in the current forecast, except
moderate confidence for coastal terminals south of Point
Conception. After 20Z, moderate confidence in the current
forecast for all terminals. There is a high to likely chance of
VLIFR to LIFR conditions at coastal terminals south of Point
Conception through 16Z, then conditions should improve through
18Z.

There is a moderate chance of moderate wind shear and turbulence
through 20Z, then there is a high chance of moderate to strong
wind shear and turbulence thereafter.

KLAX...VLIFR to LIFR conditions will continue through at least
16Z. VFR conditions should develop between 17Z and 19Z, but there
is a 25 percent chance of IFR conditions or MVFR visibilities
lingering until as late as 21Z. Any easterly winds will remain
less than 7 knots. There is a 25 percent chance of north cross
winds between 10 and 15 knots with gusts up to 25 knots between
01Z and 05Z Thursday. There is a 50 percent chance of moderate to
strong turbulence between 01Z and 08Z Thursday.

KBUR...There is a 60 percent chance of VLIFR conditions through
16Z, then VFR conditions should develop through 17Z. Northerly
winds could develop as soon as 20Z or as late as 23Z. There is a
35 percent chance of gusts as high as 35 knots between 23Z and
05Z Thursday. There is a 60 percent chance of moderate to strong
turbulence between 22Z and 08Z Thursday.

&&

.MARINE...17/808 AM.

Moderate-to-high confidence in the current forecast.

For the waters southwest through northwest of the Channel Islands
and the nearshore waters along the Central Coast, Small Craft
Advisory (SCA) level winds are likely to expected through Friday,
highest during the afternoon and evening hours. There is a
20% chance of widespread GALES each afternoon and evening through
Thursday night, but more confidence in local GALE force gusts each
afternoon and evening from Point Conception south to San Nicolas
Island. Winds will likely diminish some each day with chances of
SCA level winds decreasing to a high-to-likely (40-70%) chance
between Thursday night and Friday and to a moderate-to- high
(30-50%) chance between Friday night and Saturday. The highest
chance will likely be for an area from Point Conception south to
San Nicolas Island.

Inside the southern California bight, winds and seas will remain
below SCA levels through at least this afternoon, but there is a
moderate (30-40%) chance of SCA level winds across the western
portions. Winds will increase this afternoon and evening with a
likely chance of SCA level N winds impacting the waters from near
Malibu to Palos Verdes. Winds and seas should drop below SCA
levels for Thursday through Sunday.

Patchy dense fog will continue at times through this morning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect from noon today to 10 PM PST
      this evening for zones 88-356-362-369>375-383. (See LAXNPWLOX).
     Wind Advisory remains in effect until 4 AM PST Thursday for
      zones 349-351>353-376>381. (See LAXNPWLOX).
     Dense Fog Advisory remains in effect until 10 AM PST this
      morning for zones 350-354-355-362-366-368. (See LAXNPWLOX).
     Dense Fog Advisory in effect until 10 AM PST this morning for
      zone 548. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from noon today to 9 PM PST
      this evening for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect from 6 PM this evening to 2 AM
      PST Thursday for zone 655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Friday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Rorke
AVIATION...Hall
MARINE...Hall/Black
SYNOPSIS...jld

weather.gov/losangeles

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