565
FXUS66 KLOX 230413
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
913 PM PDT Mon Jun 22 2026

.SYNOPSIS...22/807 PM.

A shallower marine layer is expected over the next few days. A
significant warming trend will peak on Wednesday, with well above
normal afternoon temperatures, and then continue into Thursday. A
push of moisture Tuesday and Wednesday will bring at least a low
chance of rain or an isolated storm from Ventura County eastward,
and then drier conditions return. Temperatures are then expected
to cool heading into the end of the week and the weekend.

&&

.SHORT TERM (MON-THU)...22/907 PM.

***UPDATE***

Temperatures began trending warmer today with marine layer clouds
burning off relatively quickly this morning. Highs ranged from the
70s to 90s from the coasts to the interior, although the Central
Coast saw upper 60s along the coastline. High pressure centered
over New Mexico will continue to strengthen, bringing southerly
flow to the region. Expecting the marine layer to shrink in depth
and coverage over the next few days, but with continued decent
onshore flow, not expecting patchy fog to become dense as high
pressure reaches its peak Tuesday and Wednesday. Heights begin to
fall Thursday, and flow will shift from the south to more
westerly starting off the cooling trend. Temperatures were warmed
on Friday, mostly over the interior and warmer valleys where a
more gradual cool down is expected from Thursday. Chances for
isolated showers and thunderstorms were expanded to cover more of
the southern coastal waters, but chances are still low (around 5%)
for this area. Guidance is still not in agreement in terms of if
showers and thunderstorms will make it into LA and Ventura County,
but a handful of solutions suggest scattered to isolated showers
starting Tuesday afternoon for both counties.

***From Previous Discussion***

One of the main points of emphasis in the short term forecast
continues to be the building heat the next few days. A strong and
broad high pressure over northern MX and the Desert Southwest is
slowly expanding into the area, and 500mb heights continue to
increase. Guidance continues to show heights will peak around
592-593dam by midday Tuesday. This will lead to continued surface
warming that looks like it will peak Tuesday and Wednesday before
gradually cooling back down, as the high pressure flattens with
increasing troffing across the West heading into late week.

Everything remains on track with a continuation of the Heat
Advisory for Tuesday through Thursday for portions of LA County
(interior coastal plain, valleys and mountains). Afternoon high
temperatures are forecast to be mostly around 3-8 degrees above
normal, with coastal areas forecast to reach the upper 70s to
upper 80s and low to middle 90s for inland valleys. These
temperatures will lead to widespread Minor HeatRisk and areas of
Moderate HeatRisk. Admittedly under normal conditions, these
temperatures would be marginal for any heat products. However
given the current influx of visitors and numerous outdoor events
across the county, there is a higher risk and vulnerability. There
will also be a small increase in surface moisture heading into
Tuesday that may add to the discomfort from the heat. The forecast
temperatures for Thursday continue to slowly trend down model run
to model run, with a quicker intrusion of troffing from the
northwest. So, will continue to monitor trends for whether the
advisory will be continue through Thursday.

Forecast with the mid-level moisture push Tuesday into Wednesday
remains on track. The bulk of the moisture is still expected to
stay just east and south of the area, but with PWATs still
pushing up to 125-175% of normal in portions of LA County. This
moisture flux is enough to still support at least low-end PoPs
(5-15%) Tuesday afternoon into Wednesday across LA and Ventura
counties. There will be a weak perturbation wave rolling through
the area, which will help steepen mid-level lapse rates.
Otherwise, there will not be much in the way of forcing with this
setup. Latest HREF/REFS runs all point to some spotty high-based
convection developing and staying east of LA County late Tuesday
into Wednesday morning. Main concern with any convection will be
gusty outflow winds and dry lightning. The layer below 700mb will
remain very dry, so a lot of the precipitation will likely
evaporate before reaching the ground.

Other than temperatures and shower chances, no significant issues
are expected through Thursday. The marine layer will remain,
impacting the coastal plain and lower coastal valleys. However the
areal extent each night should be a little bit less than the
night before. The layer will also be more shallow, which may lead
to more morning fog impacts. As for winds, there will continue to
be the gusty southwesterly winds across interior sections, but
any advisory level winds will remain localized in the desert
foothills.

.LONG TERM (FRI-MON)...22/222 PM.

For the extended period, models continue to exhibit good synoptic
agreement. At upper levels, trough will sag across the state with
cyclonic flow over the area through the weekend. At the surface,
moderate onshore flow will continue with some enhancement of
northerly offshore gradients next weekend.

Forecast-wise, no dramatic changes to current forecast thinking.
Friday through Sunday, the cyclonic flow aloft will usher in a
cooling trend for all areas with lowering thicknesses and
increased areal coverage of marine layer stratus. Typical onshore
winds will continue across interior sections each afternoon and
evening. However, with the increase in northerly offshore
gradients, there will be an increase in northerly winds across the
Santa Ynez Range and the I-5 Corridor. Winds across the western
half of the Santa Ynez Range could approach advisory levels next
weekend.

&&

.AVIATION...23/0245Z.

At 00Z at KLAX, the marine layer was 600 feet deep. The top of
the inversion was 2800 feet with a temperature of 22 C.

High confidence in VFR TAFs for desert airfields (KPMD & KWJF).

For all other sites, low to moderate confidence in 00Z TAFs.
Timing of CIG/VSBY restrictions may be delayed by up to 3 hours
and flight minimums off by one category.

There is a 50% chance of LIFR CIGs at KPRB from 23/10-15Z.

KLAX...Moderate confidence in TAF. Timing of flight category
changes could be +/- 2 hours of current forecasts. No significant
east wind component is expected.

KBUR...Moderate confidence in TAF. VFR conditions expected.
However, there is a 10% chance of CIG/VSBY restrictions from
23/08-14Z.

&&

.MARINE...22/818 AM.

High confidence in winds and seas remaining below Small
Craft Advisory (SCA) levels through Wednesday. Local gusts
could reach 21 kts near Point Conception in the evening.
Moderate chances for SCA conditions return to the Outer Waters
Thursday afternoon/evening persisting into the weekend.
These conditions could reach into the nearshore waters along
the Central Coast and the Santa Barbara Channel at times.
Main concern is wind although seas could approach SCA levels
later into the weekend.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory remains in effect from 8 AM Tuesday to 9 PM PDT
      Thursday for zones 88-368-372-373-379-380-548. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...Phillips/SB
AVIATION...Phillips/Black
MARINE...Black
SYNOPSIS...SB/CC

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office