270
FXUS66 KLOX 231816
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1116 AM PDT Thu Jul 23 2026

Updated Aviation discussion

.SYNOPSIS...23/851 AM.

High pressure anchored over the West will keep a hot air mass in
place through early next week. The hottest temperatures are
expected for late this weekend and through the weekend. Elevated
risk for heat stress and heat illness will continue as the
prolonged hot daytime and warm overnight conditions are expected
through Monday. Gusty northerly winds will continue affect
portions of the area through Friday.

&&

.SHORT TERM (TDY-SAT)...23/840 AM.

An upper-level ridge of high pressure remains anchored over the
Western States this morning. Southwest flow aloft is waning and
the surface pressure gradients are responding to the ridge aloft
start to build over the region. Onshore pressure gradients
continue to weaken this morning, but onshore flow will remain in
place over the coming days, albeit weaker than the last several
days. The marine layer depth thin over the coming days as 500 mb
heights rise over the region.

With heights climbing and onshore flow weakening, a warming trend
will develop over the coming days. Most areas will likely see the
peak temperatures of this heat wave over the next several days.
Areas north of Point Conception are starting about 3-6 degrees
cooler than yesterday, but the air mass will catch up as onshore
pressure gradients are weakening this morning. For areas south of
Point Conception, temperatures are running about 4 to 7 degrees
above yesterday`s values currently. Heat advisories remains in
effect over most interior coastal, valley, and mountain areas,
while an extreme heat warning remain in effect across the Antelope
Valley floor. An expansion of the heat advisory is being
considered across the interior Central Coast over the next couple
of days. With temperatures starting out cooler along the Central
Coast, temperature will likely not get warm enough for advisory
criteria today, but a daytime hour heat advisory could be needed
for the daytime hours on Friday and Saturday when temperatures
soar into the upper 80s and lower 90s in some locations.

Gusty Sundowner winds will develop across southern Santa Barbara
County again this afternoon and evening. Last evening, Santa
Barbara Airport peaked at 95 degrees as breezy Sundowner winds
arrived. A wind advisory will be issued here shortly for late this
afternoon and tonight.

***From Previous Discussion***

The temperatures will be compounded by the greater than normal
humidity resulting from the warmer than normal sea sfc temps and
weak monsoon flow. The higher humidity and powerful inversion
created by the subsidence from the upper high will also bring much
higher than normal overnight lows each night.

The combination of above normal daytime highs and overnight lows
along with the higher humidities will create a dangerous
environment as people`s bodies (those without AC) will be heat
stressed day and night with no real recovery period. For all of
these reasons heat advisories are in effect through Monday
evening. Please see the product LAXNPWLOX for all of the details.

There will be a few areas and times within the Advisory Area that
will meet warning criteria, but the long-duration Advisory make
for a less complicated and easier to understand message. The risk
for heat illness is high, especially for sensitive groups like
the very young, the very old, those without air conditioning, and
those active outdoors.

The offshore push from the north will likely keep the low clouds
away from the beaches south of Pt Conception, but the onshore flow
to the east will bring the typical night through morning low
clouds and fog to the Central Coast.

The offshore push from the north will bring gusty winds to southern
Santa Barbara County, the I-5 Corridor, and the western Antelope
Valley this afternoon and evening as well as Friday Night
afternoon and evening. The SBA south coast will likely need
another wind advisory tonight and possibly again Friday night.

The upper high`s position over the 4 corners will put it in a
position for some monsoon flow leading to afternoon mtn
convection. At this time it looks like the chc is less than 10
percent, but it is not zero.

.LONG TERM (SUN-WED)...23/308 AM.

The upper high will begin to move back east on Sunday. More
importantly there will be an increase in the onshore flow and
possible return of some morning low clouds across the csts. The
low but non-zero threat of monsoon convection will remain over the
mtns. Max temps will drop a few degrees but advisory level heat
will continue.

Hgts fall some on Monday as the upper high continues to move to
the east. Onshore flow continues to increase. This will bring a
few more degree of cooling. There may be enough cooling to
consider dropping a few areas from the heat advisories, but for
now its prudent to leave them all in through Monday evening.

More cooling on Tuesday should be enough to eliminate the heat
threat. By next Wednesday highs will still be above normal but
only by 3 to 5 degrees.

Mdls remain consistent showing another round of heat developing
at the end of next week.

&&

.AVIATION...23/1810Z.

At 1701Z at KLAX, the marine layer was 1300 ft deep. The top of
the inversion was at 4600 ft with a max temperature of 28 C.

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

Moderate confidence in TAFs for KSMX and KSBP. VFR transition
could be off by 1 hour.

Fair confidence in the remainder of the TAFs with a 25 percent chc
of IFR/LIFR conds 12Z-16Z.

KLAX...Fair confidence in TAF. There is a 25% chance of OVC004
conds 12Z-16Z. No significant east wind component expected.

KBUR...High confidence in TAF.

&&

.MARINE...23/752 AM.

Widespread Small Craft Advisory (SCA) NW winds will likely
continue through the weekend across the Outer Waters, with seas
nearing 10 ft at times. Gale Force wind gusts will impact the
outer waters this afternoon through late night, and there is a 30%
chance of winds restrengthening to Gale Force levels each day
across the outer waters north of the Channel Islands through
Sunday. SCA winds will spread into the nearshore waters along the
Central Coast and Santa Barbara Channel at times through the
forecast period.

&&

.BEACHES...23/1020 AM.

A long period, southern hemisphere swell will arrive later this
week and will add to the continuing swell from Hurricane Fausto.
This swell will result in an increased risk of dangerous rip
currents across the coastal beaches, as well as elevated surf of
3-6 ft across the Los Angeles and Ventura County Beaches.
Therefore, Beach Hazard Statements are in effect through the
weekend for Los Angeles and Ventura County beaches and the Central
Coast beaches. Rip currents and elevated surf will be strongest
across south to southwest facing beaches and harbors such as Avila
Beach.

The Eastern Pacific looks to remain active with tropical systems
over the next couple of weeks. This could result in additional
southerly swells to impact the coastline.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory remains in effect until 8 PM PDT Monday for
      zones 38-88-342>345-348>358-362-366>382-548. (See LAXNPWLOX).
     Beach Hazards Statement in effect from Friday afternoon
      through Sunday evening for zones 340-346. (See LAXCFWLOX).
     Wind Advisory in effect from 3 PM this afternoon to 3 AM PDT
      Friday for zones 349-351. (See LAXNPWLOX).
     Beach Hazards Statement in effect through Sunday evening for
      zones 354-362-366. (See LAXCFWLOX).
     Extreme Heat Warning in effect until 8 PM PDT Monday for zone
      383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Saturday for
      zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Friday for zone
      650. (See LAXMWWLOX).
     Small Craft Advisory in effect from 3 PM this afternoon to 9
      PM PDT this evening for zone 655. (See LAXMWWLOX).
     Small Craft Advisory in effect until noon PDT today for zones
      670-673-676. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Friday for zones
      670-673-676. (See LAXMWWLOX).
     Small Craft Advisory in effect from 3 AM Friday to 3 AM PDT
      Saturday for zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall/Rorke
AVIATION...Rorke/Lund
MARINE...Lund/Black
BEACHES...Lund/Black
SYNOPSIS...Hall

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office