Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 291039
AFDLOX

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

.SYNOPSIS...29/238 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)...29/318 AM.

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...29/0610Z.

At 05Z at KLAX, the marine layer was 1200 ft deep. The top of the
inversion was at 4100 feet with a temperature of 18 C.

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

Areas of low clouds will affect coastal areas with the possible
exception of southwestern SBA County and much of the SLO County
coast. Low clouds will push into the Santa Ynez and San Gabriel
Valleys by midnight, and the San Fernando Valley and the valleys
of VTU Counties later tonight. Conditions will be mostly IFR to
LIFR, except locally VLIFR in the valleys/foothills. Cigs should
rise a bit in coastal areas of L.A. County tonight, so conds may
become MVFR. Skies should clear by mid morning in the valleys and
by noon across most of the coastal plain. However, cigs may
linger at the beaches of L.A./VTU Counties thru the day. Expect
clouds to return to coastal areas Wed evening.

KLAX...Moderate confidence in TAF. There is a 20% chance that
cigs will remain IFR thru 15Z. There is 20% chance that cigs will
not clear at all Wed. There is a 20% chance of an east wind
component of 7 to 9 kt from 10Z-16Z Wed.

KBUR...Moderate confidence in TAF. There is a 20% chance that
cigs will arrive as early as 09Z or as late s 13Z. There is a 20%
chance that cigs will be in the LIFR category.

&&

.MARINE...28/930 PM.

Moderate confidence in forecast.

In the outer waters, winds and seas are at Small Craft Advisory
(SCA) levels. Winds are still expected to increase to low-end
gales throughout the outer waters, with the strongest winds in
western portions of these zones. Gales are expected to continue
thru late Wed night, though they may drop below gale force at
times, particularly during the morning. Overall confidence in
gales is 70-80% in northern zones, and 50-60% in the southern
zone. If wind do not reach gale force, the will be strong SCA
levels thru Wed night. SCA level winds will likely continue
Thu/Thu night, and while winds should drop off, seas may remain
close to SCA levels Fri thru Sat.

In the inner waters N of Pt. Sal, SCA winds are likely Wed
afternoon/eve. SCA level seas are likely Wed night thu Thu night,
and there is a 40-50% chance of SCA level winds Thu afternoon/eve.
SCA conds are not expected Fri thru Sat.

In the southern inner waters S of Pt. Sal, SCA winds were limited
to far western portions this afternoon/eve, and will likely
struggle to reach the middle of the Santa Barbara Channel Wed
afternoon/night. There is 20-30% chance of gales in western
portions of the SBA Channel late Wed afternoon/Wed
night. 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 from 3 PM this afternoon to 9
      PM PDT this evening for zones 645-650. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Thursday for zones
      670-673-676. (See LAXMWWLOX).

&&

$$

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

weather.gov/losangeles

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