103
FXUS66 KLOX 291838
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
1138 AM PDT Wed May 29 2024

.SYNOPSIS...29/933 AM.

Increasing northerly flow this week is expected to cause earlier
and more complete clearing of the marine layer, leading to
slightly warmer temperatures and more afternoon sunshine. Breezy
northerly winds will develop across southern Santa Barbara County
and some interior areas each afternoon and evening.

&&

.SHORT TERM (TDY-FRI)...29/939 AM.

***UPDATE***

Marine layer depth still around 2500 feet in the LA Basin sloping
down to around 1000 feet along the Central Coast. Expecting
complete clearing of the valleys and inland coastal areas today
but some clouds may stick around at some beaches through the
afternoon, especially in the Malibu area. Some warming expected
today, mainly interior areas and Central Coast where skies are
already stratus-free.

***From Previous Discussion***

Three very similar days on tap across Srn CA. Slightly cyclonic NW
flow will prevail overhead. At the sfc there will be moderate to
strong onshore flow from the W to the E. There will be weak
offshore from the north this morning and Thursday morning from the
N to the S. Strong NW winds have developed over the outer waters
and although they will diminish some later Thursday and into
Friday will remain fairly strong.

The northwest flow has cleared the low clouds out from the outer
waters as well as the SLO county portion of the Central Coast. Low
clouds do cover the western portion of SBA county as they back
build from the Santa Ynez Vly. Meanwhile south of Pt Conception a
weak eddy has brought low clouds to the coasts and vlys. The
strong W to E onshore flow will bring slower than normal clearing
and some west facing beaches will likely not clear at all. Max
temps will not chance much just a little warming across the mtns.
The csts and vlys will remain about 6 degrees blo normal. The
interior will remain a few degrees above normal. The strong push
to the east along with some NW upper level support will bring
advisory level gusts of 45 to 50 mph to the I-5 corridor and the
western Antelope Vly foothills. At one time the SW corner of SBA
county looked like it would also have advisory level gusts but the
latest hi rez ensemble guidance only shows a brief 2 hour window
of advisory level gusts.

Look for even less low clouds tonight and Thursday as the N flow
continues. In fact it looks like all of SBA and SLO counties will
be clear. While there will be low clouds across VTA/LA counties
the north push will limit vly penetration. The increased north
flow and slightly higher hgts will also bring 2 to 4 degrees of
warming to almost all of the area.

The N/S gradient reverses on Friday and becomes onshore. A
southerly stratus surge looks likely. Low clouds will also move
back into most of the vlys. The strong W to E gradient will
continue and clearing will be slower and some beaches will not
clear at all. Max temps will fall by a few degrees. It will be
breezy across the interior in the afternoon but likely below
advisory levels.

.LONG TERM (SAT-TUE)...29/338 AM.

Look for a cooler and cloudier weekend as a sharper trof moves
over the state. The trof may produce some morning drizzle as the
marine layer lifts. Clearing may be limited across the coasts. Max
temps will cool by 1 to 2 degrees each day over much of the area.
Max temps across the csts vlys will end up 5 to 10 degrees blo
normal in the upper 60s and 70s.

The ensembles are not in the best of agreement for the days 6 and
7 period but the preponderance of solutions do favor some sort of
ridging. The moderate to strong onshore flow will continue but the
higher hgts may squeeze the marine layer down low enough to keep
some vlys clear. Its likely that the stronger marine inversion
coupled with the strong afternoon onshore flow will limit clearing
at the beaches and a few miles inland. Max temps will war each day
everywhere except the near shore area. Inland areas will warm the
most with mid 90s likely in the Antelope Vly and an out side chc
of the years first triple digit reading next Wednesday.

&&

.AVIATION...29/1837Z.

At 1723Z at KLAX, the marine layer was 2500 ft deep. The top of
the inversion was at 6900 feet with a temperature of 17 C.

High confidence in desert TAFs, with clear skies and gusty winds.

Clearing is expected in the afternoon for most sites that still
have flight restrictions, except cigs may linger through much of
the day for KCMA, KOXR, KSBA, and KSMO. Return of cigs tonight may
be off by up to 2 hours, and most will be similar or up to 300 ft
lower than last night, primarily IFR lifting to MVFR in the
morning. There is a 30% chance of IFR- LIFR cigs at KSMX from
10Z-16Z Thu.

KLAX...Moderate confidence in TAF. Cigs are expected to scatter
out between 19Z-21Z, but there is 10% chance that BKN015-BKN025
cigs will persist all day. There is a 20% chance of an east wind
component of 7-8 kt from 10Z-16Z Thu.

KBUR...Moderate confidence in TAF. There is a 10% chance of no
cigs developing tonight, and a 20% chance of BKN004 cigs and vsby
of around 2SM from 10Z-15Z Thu.

&&

.MARINE...29/757 AM.

Moderate confidence in forecast.

In the outer waters, winds are expected to increase to low-end
gales today, mainly well off the coast, and linger into tonight.
There is a 30% chance that winds will remain mostly in the Small
Craft Advisory (SCA) category. SCA level winds/seas are likely
(70-80% chance) Thu into Thu night. Conds are expected to be
below SCA levels late Thu night/Fri, though seas may be close.
SCA level conds are likely (60-70% chance) Fri night thru Sun.

In the inner waters N of Pt. Sal, SCA winds are expected to
persist into this evening, and are likely (70% chance) Thu
afternoon/eve. SCA conds are not expected late Thu evening thru
early Sat. There is 40% chance of SCA level winds in the
afternoon/eve hours Sat/Sun.

In the inner waters S of Pt. Sal, SCA winds are likely (70% chance)
in W portions of the SBA Channel this afternoon/eve, and a 40%
chance Sun afternoon/eve. Otherwise, SCA conds are not expected.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 6 PM this evening to 3 AM PDT
      Thursday for zones 378-381. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 9 PM PDT this evening
      for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect from 3 PM this afternoon to 9
      PM PDT this evening for zone 650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Thursday for zones
      670-673-676. (See LAXMWWLOX).

&&

$$

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

weather.gov/losangeles

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