956
FXUS66 KLOX 100327
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
827 PM PDT Thu May 9 2024

.SYNOPSIS...09/214 PM.

A quiet weather pattern is expected through early next week with
near normal temperatures and no rain. Increasing night and morning
low clouds are expected across coast and valleys as onshore flow
increases. Mostly minor day to day changes in temperatures are
expected through Sunday, then cooling possible Monday and
Tuesday.

&&

.SHORT TERM (THU-SUN)...09/825 PM.

***UPDATE***

Despite an increase in onshore flow and an increase in morning low
clouds (at least south of Pt Conception), max temps were generally
higher today (the Central Coast cooled some). Most max temps came
in a few degrees blo normals.

The marine layer is off to an early start and now covers the LA
county coast and is about to storm into the San Gabriel Vly. The
low clouds will likely (propelled by an eddy and increase S to N
sfc flow) end up covering all of the coasts and much of the vlys
(not the Santa Clarita) from Long Beach to Santa Maria. An
increase in the onshore push to the east will likely slow the
morning clearing by an hour or so.

An upper low retrograding into NV will bring cyclonic flow over
the area on Friday. The clear skies and steep sun angles will
bring a grip of differential heating to the mtns and this along
with the upper lows approach will destabilize the atmosphere. The
flow into the mtns will be from the NE and will be very dry (PWATs
~.2") and this will greatly limit the convective threat. Still a
non zero but less than 10 percent chc of convection tomorrow but
see the far more likely scenario being some afternoon CU
development.

Will update fcst to include extra low pops and some afternoon CU
into the mtns.

***From Previous Discussion***

A rather bland pattern next several days with very little
impactful weather and just minor day to day temperature changes.
An upper low remains centered near the UT/CO border while high
pressure is over the Pac NW. This pattern remains more or less the
same through the weekend. Falling surface pressures to the north
is beginning to push the marine layer north around Pt Conception
and expecting low clouds and dense fog to fill in there overnight.
Similar down south but with a deeper marine inversion there won`t
be much fog except near the coastal slopes. Temperatures will
remain where they are through the weekend for the most part,
within a couple degrees with no significant wind issues other than
typically breezy onshore interior winds each afternoon.

.LONG TERM (MON-THU)...09/222 PM.

Early next week a weak upper low is expected to move over the area
from the west. Along with that strengthening onshore flow will
generate a stronger and earlier sea breeze each day, possibly
requiring some low end wind advisories across the interior. The
marine layer will remain a persistent feature each day, possibly
deep enough to produce some drizzle at times with slower
clearing. High temperatures will cool a degree or two each day,
mainly coast and coastal valleys.

&&

.AVIATION...10/0016Z.

At 2332Z at KLAX, the marine layer was 1100 feet deep. The top of
the inversion was at 2800 feet with a temperature of 20 C.

Moderate confidence in TAFs. Timing of cig arrival and dissipation
may be off by +/-2 hours, and there is a 20% chance of no cigs
developing for KBUR and KVNY. Onshore afternoon winds may be
marginally stronger than normal for most coastal sites.

KLAX...High confidence in MVFR ceilings tonight, that may
returning as early as 03Z and as late as 07Z. No significant east
wind expected.

KBUR...Moderate confidence in ceilings returning as early as 07Z
and as late as 12Z. Cigs will likely be between BKN008-BKN015,
but timing of flight cat changes may be off +/-2 hours.

&&

.MARINE...09/744 PM.

The NW to W swell will continue to lower into tomorrow morning.

There is a 40-50 percent chance for Small Craft Advisory (SCA)
winds for the outer waters Saturday afternoon and night, and a 30
percent chance for the Santa Barbara Channel and the nearshore
waters of the Central Coast. Otherwise high confidence in winds
staying under SCA through the weekend. Similar conditions likely
to continue into early next week.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...MW/Rorke
AVIATION...Schoenfeld
MARINE...RK/Schoenfeld
SYNOPSIS...MW

weather.gov/losangeles

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