372
FXUS66 KLOX 292057
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
157 PM PDT Tue Sep 29 2026

***UPDATED MARINE AND BEACHES SECTION***

.SYNOPSIS...29/1223 PM.

Little change in weather conditions is expected through Thursday
with temperatures 3-6 degrees above normal. Areas of morning low
clouds and fog are possible near the coast as well. A major and
long lasting heat wave will begin Friday and last through all of
next week at least with with dangerously hot temperatures.

&&

.SHORT TERM (TDY-FRI)...29/115 PM.

...A VERY DANGEROUS AND LONG LASTING HEAT WAVE NEXT WEEK AND
LIKELY EXTENDING INTO THE SECOND WEEK IN OCTOBER...

Most of the area (except southern LA County) experienced several
degrees of warming today as pressure gradients turned briefly and
lightly offshore with some breezy north to northeast winds,
mainly in the mountains. Onshore gradients will return Wednesday,
leading to roughly 5 degrees of cooling as well as areas of low
clouds and fog in the morning.

A warming trend will return Thursday but really kick into gear
Friday and over the weekend as a long duration high pressure
system settles in over the entire West coast. Most of the
ensembles also show a light to moderate offshore flow as well
which will push the hot temperatures all the way to the coast,
especially south of Pt Conception. By Friday Downtown LA and
other intermediate coastal areas will warm into the lower 90s,
while the valleys heat up to the upper 90s to 105. These are 10-15
degrees above normal. Based on the latest guidance the chances
for heat advisories in LA/Ventura Friday are 70-90%. Central Coast
areas will not be quite as warm but still at least 5-10 degrees
above normal.

.LONG TERM (SAT-TUE)...29/139 PM.

Short term as well as longer range models continue to indicate a
very long lasting and dangerous heat wave that will likely
continue at least into the second week of October as a strong high
pressure ridge persists along the West coast. Models are also
indicating that the persistent high pressure will be accompanied
by a light to locally moderate offshore flow which means coastal
areas will be very hot as well. Based on the latest projections,
the warmer LA Valley areas will reach at least 105 by Saturday
with a 10-20% chance of 108-110. And Downtown LA is expected to
reach the mid to upper 90s by Saturday with a 20% chance of 100.
And these temperatures are expected to persist (give or take a few
degrees) through at least the end of next week and likely into
the following week (starting Oct 13).

With these numbers in mind, Extreme Heat Warnings will likely be
needed as early as Saturday for LA County. Heat advisories may
suffice for Ventura and southern Santa Barbara County through the
event, but the longer the heat wave lasts with little cooling, the
more likely it will be that advisories will need to be upgraded to
warnings. And as of now most of the projections show the Central
Coast staying just below heat advisory level but there`s at least
a 30-50% chance that temperatures and the length of the heat wave
will require at least some targeted heat advisories there.

&&

.AVIATION...29/1705Z.

At 1633Z at KLAX, the marine layer was 1200 feet deep with an
inversion top at 2400 feet with a temperature of 23 degrees C.

High confidence in VFR TAFs for KPRB, KWJF, KPMD, and KSBA. There
is a 15% chance for brief IFR cigs at KSBA after 13Z.

Moderate confidence in VLIFR conds at KSBP/KSMX tonight, with a
20-30% chance for VFR conds to prevail, higher at KSBP.

Moderate confidence in remaining TAFs. VFR conds expected through
at least 06Z, then there is a chance for IFR-MVFR conds to return,
highest chances for LA County coastal sites after 10Z.

Gusty winds will be common at all sites today.

KLAX...Moderate confidence in TAF. Gusty onshore winds will be
common this afternoon and evening. There is a 20% chance for VFR
conds to prevail. There is a 50% chance for east wind component
reaching 8 knots between 10Z-18Z.

KBUR...High confidence in VFR TAF. 20% chance for IFR conds after
12Z tonight. Gusty northerly winds will be common through this
evening.

&&

.MARINE...29/153 PM.

High confidence in Small Craft Advisory (SCA) winds and steep
seas affecting the outer waters into Wednesday morning with local
Gale Force gusts will be possible this afternoon and evening for
the outer waters south of Point Conception. Nearshore waters
along the Central coast will see SCA winds and steep seas this
afternoon and evening.

For the inner waters south of Point Conception, SCA winds are
expected across much of the Santa Barbara Channel and the inner
waters adjacent to Los Angeles and Orange Counties this afternoon
into tonight.

Southerly swell from Polo (SSE) will continue to affect the
region through this evening, decreasing fairly rapidly. These
swells will create larger waves and surf nearshore, which could
impact some south exposed harbor entrances.

Conditions are likely to improve to below SCA levels Wednesday
into next weekend, except for occasional northwest SCA winds near
Point Conception in the afternoon/evening hours.

&&

.BEACHES...29/153 PM.

The surf from Hurricane Polo has peaked and will lower rather
quickly through Wednesday, but strong rip currents may linger. The
high tide came in 1.0 to 1.2 feet above prediction today and above
7.0 feet MLLW. While the high tide will be lower on Wednesday
compared today, it will lower only a little and will likely still
be above 7.0 feet. With all that in mind, we have ended the
Coastal Flood Advisory and High Surf Advisory early, and replaced
them with a lower-tier Beach Hazards Statement to cover through
Wednesday for the rip current and tidal overflow potential.

While we will get a break from the coastal flooding concerns for
the rest of the week, another hurricane swell (from soon-to-be
Hurricane Rachel) will likely bring a larger-than-Polo south
swell to southern California for the early to middle part of next
week. Thankfully tides at that time will not be extreme, but they
should be around 6.5 feet which is high enough to cause some
concern, but it all depends on how big the surf ends up.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement in effect through Wednesday afternoon
      for zones 87-349-350-354-362-366. (See LAXCFWLOX).
PZ...Small Craft Advisory in effect until 11 PM PDT this evening
      for zones 645-650-655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 AM PDT Wednesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW
AVIATION...Lewis
MARINE...Lewis/RK
BEACHES...RK
SYNOPSIS...MW

weather.gov/losangeles

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