005
FXUS66 KLOX 301051
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
351 AM PDT Thu May 30 2024

.SYNOPSIS...30/339 AM.

A slight warming trend will occur through Friday as onshore flow
decreases beneath weak high pressure aloft. Warming will be most
pronounced away from the coast, but closer to the coast, low
clouds will continue to hug the beaches each afternoon and
evening and keep the coast near persistence. A deeper marine
layer depth will bring cooler temperatures are expected over the
weekend as onshore flow strengthens.

&&

.SHORT TERM (TDY-SAT)...29/1017 PM.

Onshore flow is weakening across the area as 500 mb heights
continue to climb this evening. Low clouds and fog are mainly
confined to the southern California bight south of Point Mugu,
while the eddy circulation reorganizes. A patch does extend into
the southern Santa Barbara County. Clouds should fill in across
the southern California bight overnight, possibly extending up the
Central Coast by Thursday morning.

A northerly surface pressure, contributing to the weaker onshore
flow, should develop gusty winds through the Interstate 5 Corridor
tonight. Though winds are struggling to develop currently, the
latest NAM-WRF solutions maintain winds kicking up rapidly after
midnight. A wind advisory remains in effect through 3 am PDT.

With onshore flow weakening, a warming trend will take shape
through Friday, especially away from the coast. The most warming
will occur across the interior portions of the area. Closer to the
coast, the low clouds and onshore flow will keep temperatures
close to persistence for the next couple of days.

***From Previous Discussion***

Troughing will return over the weekend for cooler temperatures
and likely persistent marine layer that will be slow to clear.

.LONG TERM (SUN-WED)...29/206 PM.

Following the trough passage later this weekend, weak high
pressure will return early next week for a minor warming trend,
mainly inland. Coastal areas will still be dealing with plenty of
marine layer stratus that may or may not clear completely,
especially near the coast.

The upper pattern becomes interesting the latter half of next
week as a long wave ridge sets up along the West Coast. However,
at the same time a weak upper low undercuts the ridge Wednesday
just off the Baja coast. Strong ridging across far interior
California and the Great Basin through AZ will likely bring
significant warming there and some of this warming will sneak into
the Antelope Valley and far interior SLO county with highs in the
mid 90s to near 100 beginning Wednesday. However, closer to the
coast, there will still be a moderate to strong onshore flow each
afternoon, pulling in cool ocean air (SST`s still in the high 50s
to low 60s) that will keep temperatures from climbing too much
above normal. And many beach areas will likely stay cloudy through
much of the afternoon with highs only in the mid to high 60s.
Warmer coastal valleys should get to 90 or slightly higher
starting Wednesday and lasting through the end of the week.

&&

.AVIATION...30/0056Z.

At 00Z at KLAX, the marine layer was 1900 ft deep. The top of the
inversion was at 4100 feet with a temperature of 20 C.

High confidence in desert TAFs. Moderate confidence in Central
Coast TAFs. Low to moderate confidence in all other TAFs (sites
south of Point Conception). Flight cat changes could be off by +/-
3 hours. There is a 30% chance of IFR- LIFR cigs at KSMX from
10Z-16Z Thu. Once arrived, there is a chance that CIGs do not
clear through the period for KSBA (30%), KOXR and KCMA(40%), and KSMO,
KLGB, and KLAX (20%). There is a 20% chance of LIFR conds at KOXR
and KCMA. For KBUR and KVNY, there is a 10% chance of no cigs
developing tonight, and a 20% chance of LIFR conds from 10Z-15Z
Thu.

KLAX...Moderate confidence in TAF. Flight cat changes could be off
by +/- 3 hours. Once arrived, there is a 20% chance of CIGs not
clearing through the period. 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...30/351 AM.

Moderate confidence in forecast.

In the outer waters, fairly large and steep seas were near Small
Craft Advisory (SCA) levels. Local SCA level winds will overspread
much of the waters by afternoon, then continue into late tonight.
There is 30% chance of SCA level winds Fri/Fri night in the
northern two zones (PZZ670/673). SCA level winds/seas are likely
(70-80% chance) across much of the outer waters Sat thru Mon.

In the inner waters N of Pt Sal, seas were large and steep enough
to be at SCA levels this morning. SCA level NW winds are likely
(60-70% chance) this afternoon/eve. SCA conds are not expected
late tonight thru Sat morning. SCA level winds are likely (60-70%)
chance during the afternoon/eve hours Sat thru Mon.

In the inner waters S of Pt. Sal, there is a 30-40% chance of SCA
winds in western portion of the SBA Channel in the afternoon/eve
hours today, Sat and Sun. Otherwise, SCA conds are not expected.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 9 PM PDT this evening
      for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Friday for
      zones 670-673-676. (See LAXMWWLOX).

&&

$$

PUBLIC...Hall/MW
AVIATION...Lund
MARINE...DB
SYNOPSIS...Hall

weather.gov/losangeles

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