730
FXUS66 KLOX 201823
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1123 AM PDT Sat Jun 20 2026

.SYNOPSIS...19/802 PM.

Below normal temperatures will continue through the weekend, with
a deep marine layer and a few spots of drizzle, as well as gusty
winds over the interior. A significant warming trend will start
Monday and peak around Wednesday. A push of moisture midweek will
bring at least a low chance for rain.

&&

.SHORT TERM (TDY-MON)...20/802 AM.

***UPDATE***

Morning satellite showed limited coastal marine layer clouds south
of Point Conception, potentially due to an increase in northwest
flow and some sinking motion with dry air intrusion into the
marine layer. With the clearer skies, temperatures cooled down to
the dew point temperature in many areas, leading to dew formation
on vehicles and other surfaces. The clearer skies should also
support quicker warming of temperatures through the morning.

The forecast otherwise remains on track for today, with strong
onshore flow continuing, breezy onshore winds in the afternoon,
and high temperatures this afternoon a few degrees below normal
near the coast to 5-10 degrees below normal away from the coast.

***From Previous Discussion***

Overall, 00Z models in good synoptic agreement through the short
term period. At upper levels, weak trough will continue over the
area through today then a ridge will begin to develop over the
area Sunday/Monday as high pressure builds over the desert
Southwest. At the surface, moderate to strong onshore pressure
gradients will prevail with some weak northerly offshore
gradients.

Forecast-wise for the short term, main challenge will be the
behavior of the marine layer. Marine inversion remains deep this
morning, in the 2000-2500 foot range, but stratus development is
very haphazard. So, confidence in the stratus coverage for this
morning is low to moderate as well as the potential for any
drizzle this morning. For tonight through Monday, the inversion
should gradually become more shallow. With continued onshore
pressure gradients, the stratus should behave more normally, but
exhibit a decrease in areal extent tonight through Monday. Other
than the challenging marine layer stratus, skies should remain
mostly clear through Monday.

As for temperatures, today`s highs should be very similar to
Friday although some areas could be a couple degrees warmer,
depending on stratus coverage this morning. For Sunday, all areas
will see a few degrees of warming, especially away from the coast.
On Monday, the area-wide warming trend will continue as the ridge
noses in, with coastal temperatures in the 70s and inland areas
topping out in the 80s and 90s.

As for winds, the strong onshore pressure gradients will continue
to generate gusty southwesterly winds across interior sections in
the afternoon and evening hours. However, at this time, expect any
advisory-level gusts to remain localized in the Antelope Valley
foothills. So, no wind products are expected at this time.

.LONG TERM (TUE-FRI)...20/1256 AM.

For the extended, 00Z models continue to exhibit good synoptic
agreement. At upper levels, high pressure, over Arizona and New
Mexico, peaks in strength on Tuesday then gradually weakens
Wednesday through Friday. At the surface, moderate to strong
onshore pressure gradients will continue with some continued weak
northerly offshore gradients.

Forecast-wise, main concern in the extended will be the heat. With
H5 heights peaking, Tuesday will be the warmest day of the
extended period with coastal areas 3-6 degrees above seasonal
normals and valleys/interior sections 5-10 degrees above normal.
For Wednesday, H5 heights lower slightly which will allow for a
couple degrees of cooling, but some increase in mid-level moisture
will make things feel very similar to Tuesday. On Thursday and
Friday, the gradual cooling trend will continue. Moderate heat
risk will be likely on Tuesday/Wednesday with a slight improvement
on Thursday/Friday. Given the influx of visitors to the area and
plenty of outdoor activities, will continue with the EXCESSIVE
HEAT WATCH for the Los Angeles county valleys and mountains.

Secondary concern for the extended forecast will be the potential
for some precipitation on Wednesday. Deterministic models indicate
increasing PWATs (150-200% of normal) moving into the area on
Wednesday. This matches up well with ensembles indicating high
chances of PWATs greater than 1.00 inch. However, most of this
moisture looks to be confined to 700 mb and above. So, at this
time, there is a 5-15% chance of showers/high based thunderstorms
on Wednesday just about anywhere, but with best chances over the
higher terrain. This will need to be monitored closely over the
coming days.

&&

.AVIATION...20/1820Z.

At 1000Z at KLAX, the marine layer was 1200 feet deep. The top of
the inversion was near 4700 ft with a temperature of 17 degrees
Celsius.

For 18Z TAF package, high confidence in KWJF and KPMD.

For KSMX, KPRB, KSBP, KSBA and KCMA, moderate confidence in 18Z
TAFs as timing of flight category changes could be +/- 3 hours of
current forecasts.

For KOXR, KSMO, KLGB, and KVNY, low confidence in 18Z TAFs. VFR
conditions expected during the day but timing of MVFR/IFR clouds
tonight may vary (+/- 3 hours).

KLAX...Moderate confidence in 18Z TAF. Clearing skies through the
day. For tonight, moderate confidence in return of CIG
restrictions with timing (+/- 3 hours). No significant easterly
wind component is expected.

KBUR...Moderate confidence in 18Z TAF. For tonight, there is a
40-50% chance of MVFR/IFR CIGs after 10Z.

&&

.MARINE...20/1256 AM.

For the Outer Waters, high confidence in current forecast. Today
through Wednesday, winds and seas are generally expected to remain
below Small Craft Advisory (SCA) levels. However, there will be a
10-20% chance of SCA level winds on Sunday and Monday.

For the Inner Waters (both north of Point Sal and south of Point
Conception), high confidence in current forecast. Today through
Wednesday, winds and seas are generally expected to remain below
SCA levels. However, there is a 10-20% chance of SCA level winds
across the western half of the Santa Barbara Channel tonight
through Sunday night.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Extreme Heat Watch in effect from Tuesday morning through
      Thursday evening for zones 88-368-372-373-379-380-548. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...Thompson/SB
AVIATION...Batz/RAT
MARINE...RAT
SYNOPSIS...RK

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office