988
FXUS66 KLOX 262108
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
208 PM PDT Thu Sep 26 2024

.SYNOPSIS...26/119 PM.

A quiet weather pattern will continue through the weekend with
near to slightly below temperatures for coast and valleys and
above normal temperatures farther inland. Night and morning low
clouds and fog will continue near the coast and spread locally
into the valleys. Warmer weather is expected early next week.

&&

.SHORT TERM (TDY-SUN)...26/143 PM.

A 1-2mb weakening of the onshore flow combined with earlier
clearing of the marine layer let to a few degrees of warming
today, mainly for coast and coastal valleys. A similar pattern is
expected for Friday as well as the upper low that has been
spinning just off the coast has drifted slightly farther west.

On Saturday most of the ensemble solutions swing the upper low
back to the area which should mean increasing marine layer
stratus, later clearing, and slightly cooler temperatures. Most of
those solutions linger the upper low into Sunday, but 10-20% of
the solutions show it moving east of the area by Sunday afternoon
and the latest forecast gradients also show some weakening of
onshore flow Sunday as well so possibly some earlier clearing and
a couple degrees of warming.

Otherwise, very low impact weather across southwest California
through the weekend with mostly light wind and temperatures
slightly below normal, except above normal across the Antelope
Valley, mountains, and interior SLO County.

.LONG TERM (MON-THU)...26/207 PM.

A warming trend is still expected early next week, but there
remains quite a bit of uncertainty with the magnitude and
duration. More recent ensemble solutions have been trending not
quite as hot. And even the latest GFS has backed off the heat
somewhat while onshore flow is around 2mb stronger than what it
was showing yesterday. Most of the projections still show Tuesday
being the warmest day but there`s also some uncertainty with that
as the GFS shows a 1-2mb onshore trend. Based on this guidance
the Tuesday temperatures have been lowered a few degrees, but
still getting into triple digits for the warmer valleys and close
to 90 across interior parts of the coastal plain, including
Downtown LA, and parts of the Central Coast.

The spread of model solutions past next Tuesday remains quite
large as models continue to struggle with this pesky upper low off
the coast. Most favor a modest cooling trend (3-6 degrees) for the
latter part of next week, while a smaller percentage show either
little change or even more significant cooling. There are a
handful of EPS solutions indicating a light to moderate Santa Ana
very late next week or next weekend.

&&

.AVIATION...26/1830Z.

At 1738Z at KLAX, the marine layer was 1500 ft deep. The top of
the inversion was 3900 ft with a temperature of 23 Celsius.

High confidence in desert TAFs.

Moderate to high confidence in KPRB, KBUR, and KVNY. There is a
20% chance of VLIFR- LIFR conds at KPRB 07-17Z. There is a 15%
chance of IFR conds at KBUR and KVNY 09Z-16Z.

Moderate confidence in remainder of TAFs through 03Z, then low
confidence. Timing of flight cat changes could be off by up to
+/- 3 hours and off by 1 flight cat.

For KSBP and KSMX, there is a 30% chance of VLIFR conds 03-16Z.

For KSBA, there is a 10% chance of VLIFR conds overnight, and a
30% chance of IFR cigs at worst.

For KOXR and KCMA, there is a 30% chance of cigs as early as 03Z,
and LIFR conds 08Z-15Z.

For KSMO, KLAX, and KLGB, Cigs could return as early as 03Z or as
late as 08Z. There is a 20% chance of LIFR conds 08Z-15Z.

KLAX...Moderate confidence through 03Z, then low confidence. Cigs
could arrive as early as 03Z or as late as 08Z. There is a 20%
chance of 2SM BR and BKN004 conds between 08Z-15Z. Good confidence
any significant east wind component will remain under 6 kt.

KBUR...Moderate to high confidence in TAF. There is a 15% chance
of 3SM BR and BKN005-BKN008 cigs 09Z-16Z.

&&

.MARINE...26/157 PM.

In the outer waters, low to moderate confidence in the forecast
thru Fri eve. While there may be local advisory level gusts during
the afternoon/eve hours today and Fri, winds are expected to
mostly remain below Small Craft Advisory (SCA) thru Fri night.
However, there is a 20% chance that SCA level gusts will become
widespread enough to require an advisory, especially around Pt.
Conception. From Sat thru Mon night, moderate confidence in winds
remaining below SCA levels. There is a 20% chance of SCA winds
Sat afternoon through Mon, mainly around Point Conception. There
is a 30% chance of SCA level seas late Sat thru Mon, with the
highest chance across the northern areas.

Across the inner waters north of Pt Sal, the Santa Barbara
Channel, and inner waters from Pt Mugu southward, moderate to high
confidence that winds and seas will remain below SCA levels thru
Mon night. There is a 20-30% chance of SCA level winds this
afternoon/eve, mainly in western and southern portions of the
Santa Barbara Channel, and from near Anacapa Island to Point Dume.

Patchy dense fog with visibilities of 1 NM or less may affect the
coastal waters tonight through Friday morning, with the highest
chances off the Central Coast.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...MW
AVIATION...Lund
MARINE...DB/Lund
SYNOPSIS...MW

weather.gov/losangeles

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