150
FXUS66 KLOX 142143
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
243 PM PDT Wed Aug 14 2024

.SYNOPSIS...14/907 AM.

Daytime highs will be near normal for most areas through the
weekend, followed by a warm up early next week. Patchy overnight
to morning low clouds and fog will impact coastal areas at times.
Tonight and tomorrow night gusty winds are likely across the
Santa Barbara southwestern coast and the Antelope Valley during
the evenings.

&&

.SHORT TERM (TDY-SAT)...14/242 PM.

High pressure is currently building back over the region, as the
center of high pressure located south-southwest of the region
slides eastward. 500 mb heights will peak for the short term
Thursday night at 592- 594 dam, as the center of the anti-
cyclone starts to settle over the Desert Southwest. Friday and
Saturday will see a downward trend in heights, as a trough slides
down off the coast of Oregon and Washington State.

In response to 500 mb height trends, highs will increase
marginally each day through Friday. However, even by Friday
temperatures will still be within several degrees of normal.
Expect 70s at the beaches, 80s across the inland coastal areas and
90s in the valleys. Marine layer clouds will remain minimal over
land, and mostly be confined to the beaches along the Central
Coast each night-into- morning. Saturday, as heights fall and
onshore flow picks up, temperatures will drop down to a few
degrees below normal across much of the region and marine layer
cloud coverage may increase.

Strong north-to-south pressure gradients (3 to 4 mb) this evening
and night and again tomorrow will drive Sundowner winds across
the Santa Barbara South Coast. As is typical, winds will be
strongest for the western portion of the Santa Ynez mountains and
coasts, where gusts of 35 to 50 will be common. Across the
eastern Santa Ynez mountains and foothills sub- advisory level
gusts of 25 to 35 mph are expected this evening. A Wind Advisory
will go into effect at 6 pm this evening and last through tonight
for the Santa Barbara SW Coast and western Santa Ynez Mountains.
If wind start to pick up this afternoon, the onset time of this
advisory may be advanced. These dry and warm offshore winds will
cause daytime highs across the whole Santa Barbara South Coast
(including Santa Barbara City) to be several degrees above normal
today and tomorrow, with warm temperatures lasting into the
evening.

Elsewhere, onshore pressure gradients will continue to yield the
typical southwesterly to westerly wind gusts during the afternoons
and evenings across the Antelope Valley/foothills through the
Highway 14 Cooridor. Gusts 20 to 40 mph will be common and winds
will be the strongest Friday and Saturday, when the west- to- east
pressure gradient is highest.

No monsoonal moisture is expected to reach Los Angeles County
through Thursday. Friday and Saturday, the ensembles hint at
around a 15 percent chance of some moisture reaching LA County,
but actual thunderstorm chances still remains under 5 percent for
both days. Some high clouds or cumulus cloud build ups will be
the most likely impact of any moisture reaching the region.

.LONG TERM (SUN-WED)...14/242 PM.

A modest warming trend is generally expected in the long term,
especially Monday and Tuesday, but at this point significant heat
impacts are unlikely. The region will be in between the upper low
off the coast of the Pacific Northwest and the large high
pressure center over northern Texas. Ensembles members indicate
that there is uncertainty in the exact values of 500 mb heights
over SoCal, as well as the position of the high pressure system.
This uncertainty will lowers confidence in temperatures forecasts
and monsoonal thunderstorm chances for the Los Angeles region.
Thus, there is a small (10-20 percent) chance of heat impacts by
mid- next week, and a small chance of monsoonal moisture reaching
the region each day. At present, the thunderstorms threat remains
to the southwest of Los Angeles County, this is however subject
to adjustment as the forecast evolves.

&&

.AVIATION...14/1702Z.

At 16Z at KLAX, the marine layer was 800 ft deep. The top of the
inversion was 3000 ft with a temperature of 23 Celsius.

Very high confidence in VFR conditions for KPRB, KBUR, KVNY,
KPMD, KWJF.

Chance of ceilings elsewhere, KSBP (20%) KSMX (70%) KSBA (10%)
KOXR (20%) KCMA (20%) KSMO (30%) KLAX (40%) KLGB (50%). Moderate
confidence in any ceilings being LIFR-IFR at KSBP KSMX KSBA and
IFR-MVFR elsewhere.

KLAX...High confidence in VFR through at least 06Z. 40% of
OVC008-012 ceilings forming tonight, as early as 10Z and as late
as 14Z. Southeast winds likely after 10Z, with moderate
confidence in winds staying under 8 knots.

KBUR...High confidence in VFR conditions through at least Thursday
with seasonal winds.

&&

.MARINE...14/156 PM.

For the offshore waters from the Central Coast to San Nicolas
Island (the outer waters) there is a 70% chance of gales by
tonight, and 90% chance for Thursday Night. Winds will be
strongest during the late afternoon through late evening hours.
High confidence of SCA level winds following the gales through at
least the weekend.

For the nearshore waters of the Central Coast, moderate
confidence in SCA level winds and/or steep seas through Thursday,
especially in the afternoon and evening hours. Chances of SCA
lower Friday through the weekend.

For the Santa Barbara Channel, high confidence in SCA levels winds
over the far western portion each afternoon and evening through
Thursday. There is a 50% chance of these winds filling the western
half. Moderate confidence that the eastern portion will stay under
SCA. Over the weekend, there is a 40% chance of SCA level winds
over the western half.

For the waters off of Los Angeles and Orange Counties, other than
local gusts to 20 to 25 knots in the San Pedro Channel, high
confidence in conditions staying under SCA levels.

High confidence in building short period seas through Friday
morning nearly everywhere, including the nearshore waters.

With a shallow marine layer, high confidence in dense fog with
visibilities under 1 mile effecting the Central Coast waters
through the week.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 6 PM this evening to 6 AM PDT
      Thursday for zones 349-351. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 5 AM PDT Friday for zone
      645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Thursday for
      zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT this afternoon
      for zones 670-673-676. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Friday for zones
      670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Schoenfeld
AVIATION...Kittell
MARINE...RK/Lewis
SYNOPSIS...RS

weather.gov/losangeles

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