162
FXUS66 KLOX 301655
AFDLOX

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

.SYNOPSIS...30/945 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 over the weekend as
onshore flow strengthens.

&&

.SHORT TERM (TDY-SAT)...30/954 AM.

***UPDATE***

Weaker onshore flow today and a shallower marine layer will
promote earlier clearing of the marine layer in the valleys and
warmer temperatures there as well. Along the Central Coast it`s
already clear there and some light northeast flow combined with a
full day of sunshine will warm temps there as well. Temperatures
are already trending 4-8 degrees above yesterday in both those
areas as well as the interior areas. Along the coast south of Pt
Conception a weak eddy circulation continues to spin and maintain
a solid marine layer presence. Low clouds should clear to within
a mile or two of the beaches by late morning or early afternoon.

***From Previous Discussion***

Outside of the marine layer and away from the coast, a warming
trend will take shape through Friday as 500 mb heights climb
slightly. 950 mb temperatures warm by about a degree or two across
the interior as less marine influence will make its way into the
interior valleys.

Onshore flow with troughing aloft will strengthen over the
weekend and bring a cooling trend and deepening marine layer
depth. Low clouds and fog should spread well into the valleys by
Saturday morning and likely struggle to clear from the coast.

.LONG TERM (SUN-WED)...30/438 AM.

EPS cloud cover means suggest low clouds and fog hugging the coast
into early next week as onshore flow will persist. A cooling trend
looks to bottom out on Sunday or Monday as strong onshore
pressure gradients linger. EPS temperature means climb between
Monday and next Thursday. Persistence should be the best forecast
along the coast into next week, while a warming trend will
develop, especially across the interior valleys. With EPS
temperature means climbing significantly between Tuesday and next
Thursday, temperatures break away from NBM values as EPS solutions
offer up run-to-run consistency in advertising warming away from
the coast. In fact, NBM solutions suggest a greater than 60
percent chance of the Antelope Valley seeing its first 100 degree
day. If this occurs, this would best the climatological normal
date by about a week.

&&

.AVIATION...30/1317Z.

At 12Z at KLAX, the marine layer was 1900 ft deep. The top of the
inversion was at 4400 feet with a temperature of 19 C.

Low clouds/fog were widespread in coastal areas S of Pt Conception
and in the San Gabriel Valley. Areas of low clouds and fog have
also pushed into the San Fernando Valley and portions of the VTU
County Valleys. N of Pt. Conception, there were patchy low clouds
in southern portions of the Central Coast and the southern Santa
Ynez Valley. Conds were mostly IFR to LIFR, with local VLIFR conds.
There were some MVFR cigs in coastal sections of L.A. County.

Expect skies to clear by mid morning in the valleys, by noon
across interior sections of the coastal plain, and early to mid
afternoon near the beaches. Clouds may linger at some beaches thru
the day. Expect clouds to return to the beaches this evening,
then into most valley late tonight. Conds will be mostly IFR to
LIFR, except possibly low MVFR in coastal sections of L.A. County,

KLAX...Moderate confidence in TAF. There is a 20% chance that cigs
will not clear until 22Z, and a 10% chance that conds will remain
MVFR all day. There is a 20% chance of IFR cigs from 07Z-15Z
tonight. East wind component should remain 6 kt or less.

KBUR...Moderate confidence in TAF. There is a 20% chance that cigs
will scatter out as early as 16Z. There is a 20% chance that cigs
will not arrive tonight until 11Z or later.

&&

.MARINE...30/831 AM.

Moderate confidence in forecast.

In the outer waters, fairly large and steep seas are at Small
Craft Advisory (SCA) levels. 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...MW/Hall
AVIATION...DB
MARINE...DB/Schoenfeld
SYNOPSIS...MW/Hall

weather.gov/losangeles

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