647
FXUS66 KLOX 040427
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
927 PM PDT Fri May 3 2024

.SYNOPSIS...03/855 PM.

Cooler than normal temperatures will continue through at least the
weekend as a weak storm system moves across California. Some
light precipitation is expected Saturday afternoon into very early
Sunday along with some gusty winds at times, mainly over interior
areas. A warming and drying trend will develop next week.

&&

.SHORT TERM (FRI-MON)...03/927 PM.

***UPDATE***

Today low clouds associated with the deep marine layer extended
over most coast and valley locations. These clouds were slow to
burn off south of Point Conception, lasting into the late
afternoon for Los Angeles County, and all-day for Santa Barbara
city and much of Ventura County. Temperatures were cooler than
yesterday by 2 to 5 degrees, resulting in below normal conditions
for all coasts and valleys by about 3 to 7 degrees.

Tomorrow the incoming storm system will near the region, resulting
in increasing mid to high cloud cover as the day progresses, and
temperatures will drop significantly, with the majority of highs
in the 60s. Southwest to west winds will be gusty for interior SLO
County and Antelope Valley and San Gabriel Mountains of LA County.
Wind Advisories will be issued this evening for the aforementioned
portions of LA County, starting at noon on Saturday and lasting
until 5 AM on Sunday. Gusts of 40-50 mph are expected to be
common for these areas. Saturday night, Sundowner wind will impact
much of the Santa Barbara south coast, including Santa Barbara
city and Montecito. At this time wind gusts may reach 30-45 mph,
and wind advisories will likely be needed for this area. More
widespread advisory-level winds are likely on Sunday.

Light rain is on track to begin for northwestern portions of SLO
County Saturday afternoon, spreading south during the evening and
overnight. Rain totals continue to look very minimal, with just a
few hundredth on a inch expected for Santa Barbara City, and
LA/Ventura Counties coasts, valleys, and deserts. However,
accumulations of 0.25 inch will be possible over the San Gabriel
mountains, and up to 0.50 inch over NW San Luis Obispo County.

***From Previous Discussion***

A late season storm is approaching California today and we`re
already feeling the effects of it in the form of a deeper and slow
clearing marine layer as well as much cooler temperatures. Models
have been quite consistent the last several runs indicating high
chances for rain north of Pt Conception starting Saturday
afternoon. The trajectory of the storm and the primarily westerly
low level flow isn`t as favorable a pattern for southern areas in
terms of rain but most areas should see at least some sprinkles or
light showers Saturday night. Ensembles continue to project around
a quarter inch northern areas, tapering down to a tenth or less in
the south. Most of the precip will be done before sunrise Sunday,
so most of Sunday will be dry with plenty of sunshine but still
cooler than normal with some breezy and conditions, especially
near the coast and in the mountains.

Monday will be much warmer as the storm moves into the Plains and
onshore flow weakens.

.LONG TERM (TUE-FRI)...03/217 PM.

The remainder of next week is expected to be fairly quiet with
a slow warming trend, mainly inland as California sits between a
low pressure system over the Great Basin and high pressure over
the eastern Pacific. Coastal area temperatures will be near normal
with possibly some increasing marine layer stratus by around mid
week. There is potential for more significant warming (again
mainly inland) next Friday into next weekend if the ridge over
the eastern Pacific shifts east into California as some models are
showing.

&&

.AVIATION...04/0054Z.

At 0000Z at KLAX, the marine layer was 2400 feet deep. The top of
the inversion was at 4600 feet with a temperature of 19 degrees
Celsius.

Overall, moderate to high confidence in the 00Z TAFs. MVFR CIGS
are forecast to arrive at all sites except KPRB, KPMD and KWJF
between 03Z-06Z. The CIGs are expected to linger through the
period as a storm system approaches the area, with -RA likely
after around 21Z north of Point Conception, and after 00Z-06Z
further south. There is a 30-40 percent chance that CIGs could
lift to VFR at any site between 18Z-00Z Saturday afternoon.

KLAX...Moderate confidence in the 00Z TAF. MVFR CIGs are expected
by 03Z but the arrival time could be delayed by up to 2 hours.
There is a 30 percent chance that CIGs remain at MVFR level
between 23Z-03Z. No significant easterly wind component is
expected.

KBUR...Moderate confidence in the 00Z TAF. For tonight, there is
a 30% chance that MVFR CIGs could arrive as early as 03Z.

&&

.MARINE...03/828 PM.

For the Outer Waters, moderate to high confidence in current
forecast. For tonight, Gale Warnings have been downgraded to Small
Craft Advisories (SCA) and will continue into Saturday morning.
For Saturday through Wednesday, high confidence in combination of
Small Craft Advisory (SCA) level winds and seas with a 40-60%
chance of Gale force winds Sunday afternoon through Sunday night,
and possibly into Monday, over the southern outer waters from
Point Conception to San Nicolas Island. Across all of the outer
waters, there will be a 30% chance of Gales Monday night, with
winds then gradually decreasing through Wednesday.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Winds have subsided below SCA
levels this evening. Saturday through Wednesday, there is a
60-80% chance of SCA level winds with the strongest winds during
the afternoon and evening hours. Additionally, there is a 30-40%
chance of Gale force winds Sunday night and Monday, but especiall
Monday night. SCA winds are likely to follow Tuesday through
Wednesday.

For the Inner Waters south of Point Conception, moderate
confidence in current forecast. Tonight through Saturday, high
confidence in winds and seas remaining below SCA levels. For
Saturday night through Sunday night, high confidence in a
combination of SCA level winds and seas with a 40-50% chance of
Gale force winds Sunday afternoon and Sunday night, especially
across western sections. For Monday through Wednesday, there is a
50-60% chance of SCA level winds across the western half of the
Santa Barbara Channel with high confidence in winds and seas
remaining below SCA levels elsewhere.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from noon Saturday to 5 AM PDT Sunday
      for zones 379>383. (See LAXNPWLOX).
PZ...Gale Watch in effect from Sunday afternoon through late
      Sunday night for zones 650-655-673-676. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Saturday for
      zone 670. (See LAXMWWLOX).
     Small Craft Advisory in effect until 8 AM PDT Saturday for
      zones 673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...MW/Schoenfeld
AVIATION...Smith
MARINE...RAT/Smith
SYNOPSIS...MW/Smith

weather.gov/losangeles

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