Leona Valley, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

784
FXUS66 KLOX 281403
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
603 AM PST Sat Dec 28 2024

.SYNOPSIS...28/406 AM.

An extended period of gusty northerly winds is expected through
early next week, then switching to moderate Santa Ana winds on
New Years Day through the end of the week. Warm temperatures are
expected Saturday, followed by cooling Sunday with some light
rain possible along the Central Coast. Mid next week, much warmer
temperatures are expected for the coast and valleys.

&&

.SHORT TERM (TDY-MON)...28/432 AM.

Widespread low clouds and fog in coastal areas and in the lower
valleys this morning, with abundant high clouds above. There were
patches of dense fog in many areas, but it was particularly
widespread on the Central Coast, and in the Santa Ynez and Salinas
Valleys. Dense Fog Advisories have been issued for those areas
thru mid morning. Gusty NW to N winds continued across the
mountains of SBA County, southwestern coastal sections of SBA
County, the mtns of Ventura County, the Interstate 5 Corridor,
the San Gabriel Mountains, and the Santa Clarita Valley. Winds
have dropped below advisory levels in the Antelope Valley and
foothills and in southeastern coastal sections of SBA County.
Expect winds to drop below advisory levels in most areas later
this morning, but will likely remain near of above advisory
levels thru the I-5 Corridor, across southwestern coastal SBA
County and the western Santa Ynez Range until late tonight.

Dense fog and low clouds should begin to dissipate by mid
morning and the thick high clouds will likely thin out a bit.
Expect most areas to become partly cloudy this afternoon.
Heights and thicknesses will rise across the region today as upper
high builds into the area from the southwest. Max temps should be
up several degrees in most areas from those reported on Fri, and
will generally be near normal for late December.

Upper ridging will linger over the region tonight and early Sun,
then it will flatten in response to an upper low approaching the
Pac NW Sunday. As mentioned previously, there will still be some
gusty NW to N winds across the region tonight due to decent
N-S gradients, but advisory level winds should be less widespread
tonight, confined to southwestern SBA County and the I-5 Corridor.
With the atmosphere beginning to dry and the northerly gradients
in place, expect low clouds to be less widespread tonight,
confined mainly to the Central Coast, the Salinas Valley and
coastal sections of L.A. County.

High clouds will increase across the region on Sun as the ridge
flattens. Once again, the southern end of another weakening
frontal system will move into the Central Coast Sun afternoon and
evening. This will bring a slight chance or chance of rain to SLO
County in the afternoon and evening, and possibly as far south to
about Santa Barbara Sunday evening. Expect some warming across
interior portions of L.A./VTU Counties including the Antelope
Valley and the mountains, and slight cooling north of Pt.
Conception on Sunday.

The dissipating front will fade into nothingness as it pushes S
of Pt Conception Sun night, bringing little more than a band of
clouds to L.A. and VTU Counties. However, cold air advection and
subsidence behind the front, along with increasing N-S gradients
will likely bring another round of gusty NW to N winds across SBA
County, to the mountains of L.A. and VTU Counties and through the
I-5 Corridor Sun night into Mon morning. Wind Advisories will
probably be needed for at least some of those areas. Low clouds
should be confined to southern coastal sections of L.A. County and
portions of thee Central Coast Sun night/Mon morning, though the
low clouds forecast is highly uncertain. Max temps Mon will likely
be within a few degrees of normal in most areas.

.LONG TERM (TUE-FRI)...28/602 AM.

A weak and fast moving upper trough will push into the West Coast
late Mon/Mon night, then dig into the southern Great Basin Tue.
Behind this system, strong surface high pressure will develop in
northern CA and the northern Great Basin Mon night/Tue, then it
will shift into the eastern Great Basin and the Rockies Wed and
Thu. Surface gradients between KLAX and KBFL are forecast to
increase to 7 to 9 mb offshore Mon night, with gradients between
KSBA and KBFL between 6 and 8 mb offshore. Even if there is just
modest upper support, this should generate at least advisory level
NW to N winds late Mon into Tue morning across the mtns and
adjacent south coast of SBA County, the mtns of L.A./VTU Counties,
and thru the I-5 Corridor.

Skies should be mostly clear across the region Mon night and Tue.
Max temps Tue will likely be a few degrees higher than on Mon, at
least south and west of the mountains, with some cooling in the
mountains and the Antelope Valley.

The N-S offshore component will begin to weaken late Tue into
Wed, while the W-E offshore component will increase, as evidenced
by the forecast KLAX to KDAG gradient increasing to 5 to 6 mb
offshore. This should cause the wind event to transition from a
NW to N event Mon night and Tue to a NE event Tue night and Wed,
persisting into Thu or Fri. Mostly clear skies are expected Tue
night thru Fri.

For Tue night and Wed, expect at least advisory level Santa Ana
winds in the usual favored areas, which include much of Ventura
County, the mountains of L.A. County including the Santa Monicas,
the northern and western valleys of L.A. County, and the Malibu
Coast. This wind direction typically does not produce strong winds
in the San Gabriel Valley, but that will have to be watched in
case there is a more northerly component and some mountain wave
activity (that appears unlikely at this time). Winds will likely
peak on Wed, but could remain near or above advisory thresholds
into Thu or perhaps Fri.

Max temps will rise a few more degrees Wed and Thu west of the
mountains due to compressional warming from the offshore winds.
Highs could possibly reach 80 degrees in some of the warmest
locations in the lower valleys or interior portions of the coastal
plain. It will be considerably cooler in the mtns and the
Antelope Valley. The nights will be rather chilly, especially in
interior areas sheltered from the wind, with low temps likely
below freezing in some interior valleys, and well down in the 20s
and possibly upper teens in the Antelope Valley. Some warming may
take place in the mtns and in the AV Fri as cold advection begins
to abate.

It looks as though there may be little if any rain for a large
portion of the forecast area thru least the first 10 days to two
weeks of 2025.

&&

.AVIATION...28/1216Z.

At 0805Z at KLAX, the marine layer was 1600 ft deep. The top of
the inversion was at 4200 ft with a temperature of 15 C.

Overall, low to moderate confidence in TAFs. Timing of cigs/vsby
restrictions may be off +/- 2 hours, with flight cats being off
one or two, especially during worse conditions. Cigs are also
likely to scatter and reform through the period. Dense will be
possible for coasts and valleys through 18Z Sat and again after
03Z Sun.

KLAX...Low to moderate confidence in TAF. Cigs are also likely to
scatter and reform through the period. Dense fog with vsby as low
as 1/2SM will be possible (20% chance) through 20Z. There is a
20% chance of an east wind component of 6-8 kt thru 20Z Sat.

.KBUR..Low to moderate confidence in TAF. There is a 20% chance
of dense fog with as low as 1/4SM through 18Z. Timing of cig
changes may be off by +/- 2 hours.

&&

.MARINE...28/359 AM.

For the outer waters, there is high confidence in the current
forecast. A series of large westerly swells will continue to
propagate into the coastal waters for the next several days. Winds
and/or seas will be at Small Craft Advisory (SCA) levels through
Mon night. There is a 40-50% chance that SCA level wind gusts
could continue Tue and Tue night, then good confidence conds will
fall below SCA levels Wed.

For the inner waters north of Point Sal, expect SCA conds (mainly
seas with wind at times) to persist through at least Monday
afternoon. Best chances for SCA level winds will be south of Pt.
San Luis during the afternoon/eve hours.

For the Santa Barbara Channel, wind and/or seas will be at SCA
levels much of the time through Mon afternoon. There is a 10-20%
chance of GALE force wind gusts Sun afternoon/eve. Thereafter,
conds should stay below SCA levels thru Thur morning.

For the southern inner waters, seas will be at (far western
portions of PZZ655) or below SCA levels thru tonight, then conds
should largely remain below SCA levels Sat thru Thur morning.

&&

.BEACHES...28/405 AM.

A series of large and long period west to northwest swells will
bring high surf to the west-facing beaches of the Central Coast
(10 to 15 ft, local to 18 ft) and the Ventura County (6 to 10 ft)
and Los Angeles County (5 to 8 ft) beaches for much of the
weekend, then dropping to low end high surf on Monday. Above
normal surf is also expected on west- facing beaches of the south
Santa Barbara County coast through Sun evening.

Nuisance to minor coastal flooding may continue to affect beaches
on the Central Coast and the Ventura and L.A. County Coast around
the time of the early morning high tides thru the weekend. The
risk will be the greatest early this morning for the west-facing
beaches along the Central Coast. Please reference our SRF and CFW
products for details.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory remains in effect until 10 AM PST this morning
      for zones 88-353-376-377-379-380. (See LAXNPWLOX).
     Dense Fog Advisory in effect until 9 AM PST this morning for
      zones 340-341-343-346>348. (See LAXNPWLOX).
     Coastal Flood Advisory in effect until noon PST today for
      zones 340-346. (See LAXCFWLOX).
     High Surf Advisory in effect until 3 AM PST Tuesday for zones
      340-346. (See LAXCFWLOX).
     Wind Advisory now in effect until 3 AM PST Sunday for zones
      349-351-378. (See LAXNPWLOX).
     Beach Hazards Statement in effect through Sunday evening for
      zones 349-350. (See LAXCFWLOX).
     High Surf Advisory in effect until 9 PM PST Monday for zone
      354. (See LAXCFWLOX).
     High Surf Advisory in effect until 3 AM PST Monday for zones
      362-366. (See LAXCFWLOX).
     Fire Weather Watch in effect from Tuesday morning through
      Thursday evening for zones
      288-354-355-358-362-369>372-374>376-379. (See LAXRFWLOX).
PZ...Small Craft Advisory in effect until 3 PM PST Monday for
      zones 645-650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Tuesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...DB
AVIATION...Schoenfeld
MARINE...Black/Schoenfeld
BEACHES...Black/Schoenfeld
SYNOPSIS...Smith/RS

weather.gov/losangeles

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