042
FXUS66 KLOX 080941
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
241 AM PDT Tue Sep 8 2026

.SYNOPSIS...08/231 AM.

A significant southerly swell will bring hazardous surf
conditions to the beaches through at least Tuesday. Isolated
showers will continue at times through Tuesday. The combination of
increasing heat and humidity across the area will cause moderate
to major impacts, focused over the coasts and valleys Tuesday
through at least Thursday.

&&

.SHORT TERM (TDY-THU)...08/231 AM.

Here are the top ten rainfall totals for this event:

PRELIMINARY PRECIPITATION TOTALS

.TOP RAINFALL AMOUNTS FROM ALL LOCAL AREAS
OPIDS CAMP (LA COUNTY)....................... 1.86
STUNT RANCH (LA COUNTY)...................... 1.58
CHILAO SOUTH (LA COUNTY)..................... 1.57
BEL AIR (LA COUNTY).......................... 1.56
CHILAO (LA COUNTY)........................... 1.56
MONTE NIDO (LA COUNTY)....................... 1.53
BURBANK (KBUR) (LA COUNTY)................... 1.46
SEPULVEDA CYN AT MULH (LA COUNTY)............ 1.45
BEVERLY HILLS (LA COUNTY).................... 1.42
CRYSTAL LAKE (LA COUNTY)..................... 1.41

For more totals see RRMLOX:
forecast.weather.gov/product.php?site=lox&issuedby=LOX&product=RRM

PWATs will reach 1.7 inches today as moisture from former
hurricane Marie continues to feed into Srn CA. This will lead to
a 10-20% chance of showers and thunderstorms across all four
counties today. For Wednesday, a slight chance of showers and
thunderstorms (10-15%) will continue over the northern VTA county
mtns. There will be a 5% chance will over the rest of the mtn
areas.

The main weather story for the next three days will be the heat
and humidity. An upper high will migrate to the west and will end
up over Needles by Thursday. Hgts will rise from 588 dam Monday
evening to 596 dam Thursday. At the sfc there will be weak
offshore flow this morning and Wednesday morning with only very
weak onshore flow in the afternoon. Not enough offshore flow to
create much of any canyon winds but enough to deprive the area of
the cooling sea breeze. Thursday will see a some onshore trends
which will serve to cool the csts some but the interior will
continue to sizzle. The big additional problem will be the
humidity which will be much higher than normal as PWATs will be
near 1.5" which is .86" greater than normal.

The combination of hotter than normal temps and much higher than
normal humidities has prompted the issuance of heat advisories for
the Los Angeles County beaches and coastal valleys, and the Santa
Monica Mountains today through Thursday. On Wednesday additional Heat
Advisories go into effect for the Ventura County coasts and
valleys, the Santa Clarita Valley, and all of Santa Barbara and
San Luis Obispo Counties and are valid through Thursday evening.

There is 20-30 percent chc that humidities will rise to levels
high enough to trigger heat warnings on Wednesday.

In addition to the daytime humidities the moisture will also keep
overnight low temperatures well above normal with widespread 70s
with even some 80s in the foothills).

The Central Coast will not be immune from this event as offshore
flow on Wednesday will drive some temperatures all the way to 100
to 102 degrees and most areas will end up 20 degrees or more
above normal.

.LONG TERM (FRI-MON)...08/231 AM.

Hgts should fall to about 592 dam on Friday while at the same time
onshore flow increases both to the N and E. This should lead to 3
to 6 degrees of cooling for almost all of the area. PWATs fall as
well but will still be above normal. If all of this comes to
fruition there will be no need for any heat products. There is,
however, a 20 percent chc that this cooling may be slower to
develop and there will be a need for one more day of heat
headlines.

The ridge flattens out over the weekend and onshore flow
continues. Look for 3 to 6 degrees of cooling on Saturday which
should bring most temps to a few degrees blo normal. Sunday`s
temps will be similar to Saturdays. PWATs should drop down to
normal as well.

Onshore flow weakens some on Monday and this should lead to 1 or 2
degrees of warming.

&&

.AVIATION...08/0551Z.

At 0502Z at KLAX, there was no marine layer. A surface inversion
had a top near 1800 feet, with a temperature of 27 degrees C.

Low to moderate confidence in the Central Coast sites. There is a
40 percent chc of no dense fog at KSMX and a 20 percent chc of
dense fog at KSBP.

Good confidence in no low clouds for the rest of the sites.

There is a slight chance of showers and thunderstorms for all
areas from 12Z to 00Z.

KLAX...Good confidence in TAF. There is a slight chance of -SHRA
and a non-zero chance of -TSRA 12Z-00Z. Any showers could produce
locally gusty winds and brief moderate to heavy rain. No
significant east wind component expected.

KBUR...Good confidence in TAF. There is a slight chance of -SHRA
and a non-zero chance of -TSRA 12Z-00Z. Any showers could produce
locally gusty winds and brief moderate to heavy rain.

&&

.MARINE...08/233 AM.

There will be a slight chance of thunderstorms over portions of
the waters today, mainly in the western Santa Barbara Channel and
northward.

For the Outer Waters, below Small Craft Advisory (SCA) level
winds and seas are expected into Wednesday, except for local
advisory level gusts around Point Conception each afternoon and
evening. Wednesday night through Friday, SCA winds are likely
much of the time, especially over the southern zones near and
south of Point Conception.

For the Inner Waters north of Point Sal, there is a 60% chance
of SCA winds Thursday afternoon through Friday.

For the Inner Waters south of Point Conception, localized areas of
borderline SCA winds are likely this afternoon and evening,
nearshore along the LA County coast and through the San Pedro
Channel. The focus for SCA winds will shift to the western Santa
Barbara Channel Thursday into the weekend.

A south swell is impacting the area, although beginning to
subside. This swell may still cause increased currents and surges
in vulnerable harbors. Breaking waves may impact some south facing
harbor entrances, particularly for Ventura and Los Angeles
Counties.

&&

.BEACHES...07/726 PM.

There is a slight chance of thunderstorms across the Los Angeles
County beaches through this evening. Any thunderstorm that forms
could produce local gusty and erratic winds and seas, brief heavy
downpours, and dangerous cloud-to- surface lightning. Additional
thunderstorm chances are expected early Tuesday morning through
the afternoon hours, affecting mainly the Central Coast and Santa
Barbara South Coast, but with a non-zero chance further south.

A south swell from tropical storm Marie is beginning to subside,
but with continued coastal impacts likely through Tuesday. High
surf will affect south- facing beaches of Ventura and Los Angeles
counties, peaking at 4-7 feet with local sets to 8 feet through
Tuesday afternoon. Very strong rip currents will continue as
well. The highest surf is along Zuma Beach and the Long Beach
area. HIGH SURF ADVISORIES remain in place for Los Angeles and
Ventura Counties, with BEACH HAZARDS STATEMENTS in effect for
Santa Barbara and San Luis Obispo Counties.

Moderate coastal flooding has occurred and will continue around
high tides for south facing shores. The actual observed tides
have been running about 6 inches above predictions, with the
evening tides likely near or exceeding 7 feet. As the surf begins
to diminish, the coastal flooding will subside somewhat.

Expect beach erosion, flooded sandy beach areas, bike paths, and
parking lots, as well as low-lying roads. Of particular concern
will be the Alamitos Peninsula area in Long Beach where coastal
flooding will potentially cause local damage to structures near
times of high tide. Other areas of concern the next couple of
days include Catalina Island, and Oxnard to Malibu (including the
Pacific Coast Highway near Point Mugu). COASTAL FLOOD ADVISORIES
remain in effect for Los Angeles and Ventura Counties where the
best combination of tides and waves will occur, but Santa Barbara
and San Luis Obispo Counties could also see some isolated issues.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory in effect from 10 AM Wednesday to 8 PM PDT
      Thursday for zones 38-88-340>358-374-375. (See LAXNPWLOX).
     Coastal Flood Advisory in effect until 11 PM PDT this evening
      for zones 87-354-362-366. (See LAXCFWLOX).
     High Surf Advisory in effect until 11 PM PDT this evening for
      zones 87-354-362-366. (See LAXCFWLOX).
     Beach Hazards Statement in effect through this evening for
      zones 340-346-349-350. (See LAXCFWLOX).
     Heat Advisory in effect from 10 AM this morning to 8 PM PDT
      Thursday for zones 362-366>373-548. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...Rorke
AVIATION...Rorke
MARINE...Black/Lund/Ciliberti
BEACHES...RS/Gomberg/KL/CC
SYNOPSIS...Munroe/Schoenfeld/Ciliberti

weather.gov/losangeles

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