-- Discussion containing changed information from previous version are highlighted. --
986
FXUS66 KLOX 242100
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
200 PM PDT Fri May 24 2024

.SYNOPSIS...24/946 AM.

Strong onshore flow and a deep marine layer will make recurring
night through morning low clouds, fog, and patchy drizzle, with
low clouds reaching the foothills. There is a twenty percent
chance of a light rain shower this afternoon at mountain locations.
Expect better clearing and warmer temperatures starting Sunday.

&&

.SHORT TERM (TDY-MON)...24/134 PM.

Low clouds continue to blanket the non mountainous portions of
Ventura and Los Angeles Counties, but there was good clearing in
Santa Barbara (except for a strip along the south coast) and San
Luis Obispo Counties. Temperatures are up a couple of degrees from
this time yesterday along the south coast where the sea breeze is
a little less strong and there was some better clearing. HREF
still suggesting a 20% or less chance of a light shower in
mountains this afternoon.

Still expecting the strong onshore gradients to produce advisory
level winds in the Antelope Valley and the adjacent foothills, and
Wind Advisories are in effect there for this afternoon and
evening. Winds may get close to advisory levels as well through
the Highway 14 Corridor in the mountains of L.A. County, and
advisories may have to be extended into that area as well.

N-S gradients will increase across SLO and SBA Counties this
afternoon and evening, and there will be some subsidence once the
trough axis passes that area. Expect gusty NW winds to reach
advisory levels across much of southwestern SBA County this
afternoon and evening. The Gaviota RAWS has already been showing
offshore wind for the last several hours.

Expect a switch to a broad NW flow pattern aloft later tonight
and Sat. Models show some reduction in low clouds tonight as cooling
aloft should help wipe out any weak marine inversion. Expect a
rather less solid and rather haphazard cloud field tonight and Sat
morning, and there should be more in the way of sunshine in most
areas Sat afternoon. Due to increased sunshine and small height
rises, expect a couple of degrees of warming in most areas Sat,
though temps should still be below normal. Strong N-S gradients
will likely produce another round of advisory level winds across
the southwestern coast of SBA County and the western Santa Ynez
mtns late Sat afternoon and evening.

The flow aloft will become even more zonal Sat night and Sun, and
heights will rise a bit Sunday. Expect the marine layer to
reorganize, but be less deep, with night thru morning low clouds
and fog confined mainly to coastal and valley areas Sun morning.
Expect mostly sunny skies in most areas Sunday afternoon, with a
few degrees of warming due to height rises, warming at 950 mb and
slight weakening of the onshore gradients. High temps will likely
rise into the 80s in the Antelope Valley, and could even approach
80 degrees in the Salinas and Cuyama Valleys. Temps should rise
into the mid to possibly upper 70s in the warmest valley locations
in L.A. and Ventura Counties.

Monday will be similar to Sunday, with the NBM mean solutions
building the ridge which should allow a little more clearing and
warming. Downtown LA should see the afternoon high at a seasonal
low 70s, while Paso Robles could make it into the low 80s, and
Antelope Valley into the high 80s.

.LONG TERM (TUE-FRI)...24/134 PM.

Models are in fairly good agreement in showing an upper low
moving toward the coast of southwestern Canada Tue, then dropping
slowly southeastward with a trough extending into northern
California. Our area will see the effect of that feature in a
weakening of the ridge on Wednesday and a more zonal pattern on
Thursday and Friday. EFI wasn`t pointing to anything
climatologically abnormal in the long term, but the NAEFS
percentile was showing stronger than normal winds over the waters
along the coast Wednesday. Overall, expect rather benign weather
Tue thru Fri, with areas of night/morning low clouds in coastal
and most valley areas.

&&

.AVIATION...24/1859Z.

At 1755Z at KLAX, the marine layer was 4500 ft deep. The top of
the inversion was at 5500 feet with a temperature of 11 C.

High confidence in desert TAFs.

Low confidence in remainder of TAFs. There is a 60-70% chance of
MVFR CIGs 03Z-06Z Sat, except for KSBA, KOXR, and KCMA where
there is a 20% chance of MVFR cigs developing after 10Z.

KLAX...Low confidence in TAF. There is a
30% chance of BKN025 conds as early as 02Z Sat, followed by a 60%
chance of BKN025 cigs until 21Z. Flight Cat changes could be off
by +/- 2 hours. Low confidence in winds from 12Z-18Z Sat, with a
30% chance of the SE wind reaching 10 kts.

KBUR...Low confidence in TAF. Flight cat changes could be off by
+/- 2 hours. Cigs are likely to bounce between BKN015-BKN025
after 07Z Sat.

&&

.MARINE...
-- Changed Discussion --
24/159 PM.

Moderate to high confidence in forecast, with higher confidence
in winds relative to seas.

Across the outer waters, Small Craft Advisory (SCA) level winds
and low-end SCA seas are expected to persist through late Saturday
night. Sunday and Monday afternoons/nights there is a 50-70%
chance of SCA winds. Starting Tuesday morning, chances of SCA
winds will increase to a 60-80% chance, with a 30-40% chance of
Gale Force winds Tuesday night through Wednesday.

Across the nearshore waters along the Central Coast, there is an
80% chance of SCA conds this afternoon and night, and again on
Saturday afternoon and night. There is a 30-40% chance of SCA
winds during the afternoon and evening hours Sunday and Monday.
Tuesday afternoon through Wednesday, SCA level winds are likely
(60-70%, with a 20-30% chance of Gale Force winds.

Across the southern inner waters, there is a 70-80% chance of SCA
level winds across the the Santa Barbara Channel (strongest in the
western portion) this afternoon and evening, and again Saturday
afternoon and evening. There is a 30% chance that there will be no
break in SCA winds for the western and central portions of the
channel Saturday morning. South of the Channel Islands, there is
a 50-70% chance of SCA level winds pushing into the western
portion of the southern inner waters this evening with choppy SCA
seas. There is a 30-40% chance of this reoccurring Saturday
evening. Winds and seas should drop below SCA levels Sunday
through Tuesday.
-- End Changed Discussion --

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect until 9 PM PDT this evening for zones
      349-351-381>383. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Saturday for
      zones 645-650. (See LAXMWWLOX).
     Small Craft Advisory in effect from 9 PM this evening to 3 AM
      PDT Saturday for zone 655. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Sunday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...DB/jld
AVIATION...Schoenfeld
MARINE...Lund/Schoenfeld
SYNOPSIS...jld

weather.gov/losangeles

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