601
FXUS66 KLOX 060421
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
921 PM PDT Tue May 5 2026

.SYNOPSIS...05/1223 PM.

Cloudy, cool, and breezy conditions today will be followed by a
warming and drying trend for Wednesday through at least Mother`s
Day Weekend. There is a chance for widespread high temperatures to
be in the 90s Saturday through Monday, with the valley locations
generally the warmest.

&&

.SHORT TERM (TUE-FRI)...05/917 PM.

***UPDATE***

Another cool day as the low system lingered over the area.
Overall, we ended up with quite a few areas seeing very light rain
totals below 0.05 inches, and some pockets of higher totals near
0.25 inches. Expecting dry weather now through the week as high
pressure builds in. Marine layer clouds may return to some coasts
tonight, possibly pushing into the coastal valleys of the LA
Basin and the Salinas Valley. A Catalina Eddy is forecast to
develop in the early morning hours, supporting clouds for the LA
area and possibly expanding north towards Ventura County. Looking
at an expanding marine layer over the next few days, which will
serve to keep the coasts cool. High pressure will allow the
interior to warm, and compress the marine layer keeping low clouds
and patchy fog closer to the coasts. Temperatures will approach
90 degrees for the deserts and valleys towards the end of the
week.

***From Previous Discussion***

Partly cloudy to cloudy skies are present across the region with
higher ceilings than the typical marine layer low clouds.
North to northeast flow will lead to continued cumulus cloud
formation and scattered light showers will be possible through
this evening, focused over the north facing slopes of the
mountains. The low pressure system is continuing to slide to the
southeast and as it exits the region, gusty west to northwesterly
winds is impacting the coasts through this evening, with the
strongest winds (near advisory level) across the Santa Barbara
County south coast and the Ventura County Coast.

A pattern shift in the weather pattern will begin Wednesday.
Behind the low pressure system, a ridge of high pressure will
build, likely peaking in strength Sunday through early next week.
Slight warming on Wednesday will be followed by a more
significant increase for Thursday and Friday, when highs in the
mid 70s to mid 80s will be common. Overnight into morning marine
layer clouds will return for some locations tonight and dense fog
will be possible Thursday and Friday morning.

.LONG TERM (SAT-TUE)...05/252 PM.

Temperatures will continue to trend upwards over the weekend as
the ridge strengthens. The ridge will likely peak Sunday through
early next week, when 500 mb heights have the potential reach
590-591 dam. This would be in the 99th percentile of 500 mb
heights for this time of year. In addition, there is a chance of
weak offshore flow from the north (Saturday), shifting northeast
(Sunday and Monday). If this flow pattern develops, then it would
result in further warming of high temperature across the valleys,
and perhaps more impactful, across the beaches (where conditions
generally are quite cool in May). Ensemble models and local
temperature study data indicate that high temperatures may be
widespread in the mid 80s to mid 90s (10-20 degrees above normal),
with local 100+ temperatures possible for the warmest valleys.
Saturday through Monday look to be the main peak of heat, just
right for a very warm Mother`s Day weekend. However, a significant
heatwave is not guaranteed, if surface pressure gradients end up
onshore, as several ensemble models show, heat will be dampened by
a seabreeze at the coasts.

&&

.AVIATION...06/0232Z.

At 00Z at KLAX, there was a deep moist layer up to 8600 ft.

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

Moderate confidence in remaining TAFs. Patchy MVFR CIGs possible
across the LA Basin (10Z-18Z) and for KSMX, KSBP. There is a 20%
chance low clouds do not develop at KPRB. For all sites with
forecasted CIGs, low confidence in arrival times.

KLAX...Moderate confidence in TAF. Low confidence in arrival times
of cigs. East winds are possible from 09Z to 15Z, and there is a any
east wind component should remain below 10 kts.

KBUR...Moderate confidence in TAF. 30% chance of IFR-MVFR CIGs to
develop 10Z-15Z Wed. Otherwise, VFR conditions with no wind
issues are expected.

&&

.MARINE...05/735 PM.

Small Craft Advisory (SCA) winds will be common across the
western Santa Barbara Channel and near the Channel Islands
through this evening.

From Wednesday through Saturday, SCA level NW winds are expected
to strengthen each day and will peak Friday afternoon and evening.
These winds are likely to reach 20 to 30 kts across the outer
waters. There is about a 15% chance of GALE Force winds during
this timeframe. SCA level winds are also likely at times across
the nearshore waters along the Central coast and into at least
western portions of the Santa Barbara Channel.

Short period seas will build during this timeframe especially
across the outer waters - reaching 10 feet by Friday then peaking
up to 11 feet Friday night through Saturday night.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Wednesday for
      zone 650. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Thursday for
      zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Phillips/Schoenfeld
AVIATION...Phillips
MARINE...Black/Sirard
SYNOPSIS...RS

weather.gov/losangeles

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

NWS Los Angeles (LOX) Office