879
FXUS66 KLOX 020304
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
804 PM PDT Thu Oct 1 2026

.SYNOPSIS...01/131 PM.

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 (THU-SUN)...01/804 PM.

***UPDATE***

Latest satellite and surface observations indicate mostly clear
skies across the area except for some stratus/fog along the
immediate coast. Current sounding data indicates marine inversion
in the 800-1300 foot range. No significant winds are observed.

Forecast-wise for the immediate short term, no significant issues
are expected. Weak onshore gradients will continue through the
overnight hours, allowing for stratus/fog to become a bit more
widespread across the Central Coast as well as the Ventura/LA
coastal plain. With H5 heights remaining stagnant overnight, do
not expect any appreciable deepening of the marine inversion. So,
most stratus/fog should remain confined to the coastal plain.
Other than the stratus, skies should remain clear overnight.

For the remainder of the short term period, main focus will be a
long duration heat wave. The details from the short term
discussion below are still valid.

***From Previous Discussion***

***A VERY DANGEROUS AND LONG LASTING HEAT WAVE FRIDAY THROUGH AT
 LEAST NEXT WEEK AND LIKELY EXTENDING INTO THE SECOND WEEK IN
 OCTOBER***

No significant changes to the short or long term forecasts. A
dangerous heat wave will begin Friday and last through at least
next week as a strong high pressure system sets up over the
eastern Pacific and West coast. Pressure gradients are already
starting to weaken today and that trend will continue through
Saturday morning, resulting in offshore gradients to the east and
north in the -2 to -4 range. So while this is an offshore
scenario in October, it`s not a traditional Santa Ana as the upper
support is not sufficient for persistent gusty winds, though there
will be brief periods of some sub advisory level north to
northeast winds at times. However, in typical Santa Ana fashion,
this heat wave will include the beaches, at least south of Pt
Conception.

Temperatures will ramp up quickly Friday by 5-10 degrees and
"peak" Saturday, though "peak" is misleading because day to day
high temps will likely not change much at least through early next
week. During this heat wave, warmer valley highs are expected to
be 102-107, Downtown LA 99-103, and coastal areas from Santa
Barbara to LA 90-98. These are 15-20 degrees above normal.

It will be warming in SLO and northern Santa Barbara Counties as
well but delayed by a day. By the weekend expecting highs away
from the beaches to reach the low to mid 90s and lower 100s in the
interior. Heat advisories have been issued for these areas
Saturday and Sunday. These may need to be extended in certain
areas next week but models have been showing just enough cooling
early next week to allow the advisories to drop off.

.LONG TERM (MON-THU)...01/219 PM.

This period will feel a lot like this coming weekend, though
there are still some model solutions indicating a little more
upper level northeast wind support and subsequently even hotter
temperatures. This would be in the Wed-Fri period, so there is the
potential for even hotter weather later next week with a better
chance of breaking daily temperature records. Longer range models
are starting to at least hint at some cooling next weekend.

&&

.AVIATION...02/0034Z.

At 2352Z at KLAX, the marine layer was 900 ft deep. The top of
the inversion was near 2600 ft with a temp of 29 C.

High confidence in VFR TAFs for KPRB, KBUR, KVNY, KWJF and KPMD.

Moderate confidence in remaining TAFs. Timing of change groups
may be off +/- 2 hours. VLIFR conds expected for Central Coast
sites, with LIFR for KSBA. IFR to low MVFR for the Ventura and LA
Coastal sites.

KLAX...Moderate confidence in the 00Z TAF. Arrival and clearing
times of IFR CIGs may be off by 2 hrs. CIGs may be intermittent
between 07Z to 16Z. No significant east wind component expected.

KBUR...High confidence in the VFR 00Z TAF. No wind issues
expected.

&&

.MARINE...01/722 PM.

Generally quiet conditions expected across the coastal waters
through the forecast period. Localized Small Craft Advisory (SCA)
gusts may occur each afternoon and evening near Point Conception,
off the coast of Point Dume, and across the San Pedro Channel.

&&

.BEACHES...01/1245 PM.

While we will get a break from the coastal flooding concerns for
the rest of the week, another hurricane swell (from 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. Stay tuned for future updates.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Extreme Heat Warning in effect from 10 AM Friday to 8 PM PDT
      Thursday for zones 38-87-88-349>358-362-366>375-548-550. (See LAXNPWLOX).
     Heat Advisory in effect from 10 AM Saturday to 8 PM PDT
      Sunday for zones 341>345-347-348. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...MW/Thompson
AVIATION...Ciliberti
MARINE...Black/Ciliberti
BEACHES...RK/DB
SYNOPSIS...MW

weather.gov/losangeles

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