674
FXUS66 KLOX 270326
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
826 PM PDT Sun May 26 2024

.SYNOPSIS...26/739 PM.

A May gray into June gloom pattern is expected through next
Sunday. Varying amounts of night and morning low clouds and fog
will affect the coast and valleys, otherwise mostly clear skies
will prevail. Temperatures will be a few degrees below normal
into early this week, then warming to near normal or a few
degrees above normal for mid week and into next weekend.

&&

.SHORT TERM (SUN-WED)...26/825 PM.

At upper levels, a weak upper level trough of low pressure
will prevail across California, but heights gradually rise
across our region the next couple of days. Near the surface,
strong onshore flow will continue with LAX-Daggett pressure
gradient expected to peak in the +7 to + 8 mb range each afternoon
through Wednesday. Current satellite imagery showing a somewhat
chaotic marine layer cloud pattern this evening, with clouds
lingering across western Ventura county, as well as portions of
the Santa Barbara south coast and Central Coast. The marine layer
depth is expected to gradually shrink the next couple of nights
due to the rising heights, with low clouds expected to fill in
across most coastal and coastal valley locations. The low clouds
should clear to or off the coast for the most part each afternoon,
with Santa Catalina Island probably having some low clouds linger
thru much of the day.

Gusty onshore winds are somewhat weaker and less widespread
across the Antelope Valley this evening, however still seeing
some local wind gusts to around 40 mph near Lake Palmdale.
Gusty NW winds are also less widespread tonight across southwest
Santa Barbara county. Still on track to see a warming trend
on Monday, with little change into Tuesday and Wednesday. Warming
will be most noticeable across the interior, especially the
Antelope Valley where highs will climb to around 90 on Monday and
Tuesday.

Sundowner winds expected to be fairly weak through Monday night,
then strengthen on Tuesday night and Wednesday night, potentially
reaching advisory levels across western portions. W-NW winds
are also expected to ramp up across the I-5 corridor and Antelope
Valley Tuesday night through Wednesday, potentially reaching
advisory levels.

*** from previous discussion ***

Temps should remain several degrees below normal thru Tue, except
increasing to a few degrees above normal for the interior areas
including some of the mtns and into the Antelope Vly. By Wed,
temps will turn a little bit warmer with highs near normal to a
few degrees above normal for many areas. Highs for much of the
inland coast, vlys and lower mtns should be in the 70s to lower
80s Mon and Tue and in the mid 70s to mid 80s Wed. The warmest
areas should be in the Antelope vly, with highs in the upper 80s
to around 90 each day.

.LONG TERM (THU-SUN)...26/158 PM.

Not a whole lot of change can be expected in the extended period.
It looks a broad NW flow aloft with H5 heights around 583-584 dam
will prevail Thu. Flat upper level ridging is forecast for Fri
with H5 heights around 584 dam, then weak upper level troffiness
should persist Sat and Sun with H5 heights around 582-584 dam.

Good onshore pressure gradients to the N and E will help to keep
the marine layer pattern over the forecast area Thu thru Sun.
Varying amounts of night and morning low clouds and fog are
expected for the coast and vlys, moving farthest inland Sat and
Sun as the marine inversion deepens. Otherwise, mostly clear skies
can be expected thru the period.

Just minor day-to-day changes in temps are forecast, with
readings ranging from a few degrees below normal to a few degrees
above normal depending on location, but the warmest temps should
be for the interior vlys, lwr mtns and deserts. Afternoon highs
for the inland coast and vlys should be in the 70s to around 80,
except into the 80s for the interior vlys as well as lower mtns,
and generally in the low to mid 90s in the Antelope Vly.

&&

.AVIATION...26/2340Z.

At 2340Z at KLAX, the marine layer was 3000 ft deep. The top of
the inversion was at 5600 feet with a temperature of 16 C.

High confidence in desert TAFs and low confidence in
coastal/valley TAFs. Lower confidence for coastal/valley sites due
to uncertainties in the behavior of the marine layer stratus.
Timing of flight cat changes could be off by +/- 4 hours (greatest
uncertainty after 03Z Mon) and CIGs will range between IFR/MVFR
levels. KBUR and KVNY have a 30% chance of remaining VFR through
forecast period. Upon return tonight (after 02Z Mon), there is a
30% chance of IFR CIGs for sites south of Point Conception, and
increasing chances (70%) of LIFR conds for KSBP and KSMX.

KLAX...Low confidence in TAF. Timing of flight cat changes could
be off by +/- 2 hours. There is a 30% chance of IFR cigs late
tonight. No significant easterly wind component is expected.

KBUR...Low confidence in TAF. Timing of flight cat changes could
be off by +/- 3 hours. There is a 30% chance of conds remaining
VFR through forecast period,

&&

.MARINE...26/737 PM.

Moderate to high confidence in forecast.

Across the outer waters, Small Craft Advisory (SCA) level winds
are expected to drop off late tonight. SCA winds are likely to
redevelop Monday afternoon and then persist much the time through
Thursday. There is a 20-30% chance (highest for the northern
waters) of Gale Force winds Tuesday afternoon and night. Then for
all the outer waters there is a 50-60% chance of gales Wednesday
afternoon through Wednesday night. On Tuesday seas will build to
SCA levels and remain steep and choppy through at least Thursday
night.

Across the nearshore waters along the Central Coast, SCA level
winds are expected to drop off by 900 PM. There is a 20-30%
chance of SCA winds again during the afternoon/evening hours on
Monday. Tuesday afternoon through Wednesday night, SCA level winds
and seas are likely (60-70%), with a 15-25% chance of Gale Force
winds Wednesday afternoon/evening. SCA seas may linger as late as
Thursday night.

Across the southern inner waters, there is a 30-40% chance of SCA
level winds across the western portion of the Channel each
afternoon and evening through Tuesday, followed by a 60-70%
chance on Wednesday, with a 20-30% chance of gales. South of the
Channel Islands, winds are expected to remain below SCA levels
through at least Wednesday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Monday for
      zones 645-670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Gomberg/Sirard
AVIATION...Gomberg/Schoenfeld
MARINE...Lund/Schoenfeld/Smith
SYNOPSIS...Sirard/Smith

weather.gov/losangeles

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