853
FXUS66 KLOX 061520
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
820 AM PDT Thu Jun 6 2024

.SYNOPSIS...06/334 AM.

Well above normal temperatures will continue today, for areas
away from the coasts. The marine layer will again bring night
through morning low clouds to the coasts and valleys. While above
normal temperatures are expected over the interior through
Saturday, closer to the coast, highs will be moderated by the
low clouds and moderate to strong onshore flow.

&&

.SHORT TERM (TDY-SAT)...06/819 AM.

***UPDATE***

The forecast is well on track, and no changes have been made to
the ongoing forecast.

***From Previous Discussion***

The upper level ridge is expected to persist over the region
today, followed by gradually falling heights each day through
Saturday. The warm airmass aloft and compressional heating will
yield another day of well above normal temperatures for inland
areas, that will be similar to yesterday. The EXCESSIVE HEAT
WARNING for the Antelope Valley and HEAT ADVISORIES for interior
San Luis Obispo county, the Cuyama Valley and the western range of
the San Gabriel Mountains are all still in effect through 8 PM
tonight. Daytime highs are likely to be in the upper 60s through
the mid 70s for coasts, up to the low 90s for valleys, and
up to 104 degrees for deserts and other far inland locations. The
daily maximum temperature record is in play today for Palmdale
Airport, which currently stands as 102 degrees in 1985. Friday and
Saturday a cooling trend is expected for inland areas, with
little temperatures changes for coasts and valleys. Saturday
temperatures are likely to be within a 3 to 6 degrees of normal
for much of the region.

The marine layer depth is currently around 1700 feet, and low
clouds and fog are well into the coasts and valleys. Clouds are
beginning to spread into the Santa Clarita valley, as a result of
the prevailing westerly flow. Marine layer clouds are expected to
burn off for valleys by midday. However many beach and nearshore
locations will say socked in today, as the onshore LAX to DAG
gradient will trend upward to near 9mb. Friday and Saturday are
expected to see very similar behavior of the marine layer as
little variation is expected in the strong onshore pressure
gradients. However the marine layer may deepen somewhat each day,
increasing it`s inland extent, as the ridge breaks down.

The strong onshore gradient through Saturday will drive gusty
southwesterly winds for the Antelope Valley foothills/western
portion during the afternoons and evenings. Winds will be near
advisory level with local gusts up to 45 mph during peak times.
Wind Advisory(s) may be needed, with the highest chance for
Friday. Models have continued to trend downward for upper level
moisture, thus the chance of showers over the mountains remains
very low (< 10%).

.LONG TERM (SUN-WED)...06/331 AM.

Latest model runs continue to align well for the overall synoptic
pattern in the extended period. The GFS and ECMWF both show a
trough developing over the region Sunday, followed by a weak low
pressure system to the south or southwest of SoCal, that will
slowly travel eastward through Wednesday. For the near surface
flow, moderate to strong onshore gradients are expected to
continue, maintaining the June Gloom pattern and driving gusty
southwesterly winds each afternoon across interior areas.

Low impact weather with no significant hazards are anticipated
through mid next week. Temperatures will generally be coolest on
Sunday, followed by a very slight warming trend for most areas
through Tuesday. Falling upper level hgts may lift the marine
layer, thus overnight and morning drizzle will be possible through
the period, with the highest chances Monday and Tuesday night.

&&

.AVIATION...06/1210Z.

At 1105Z at KLAX, the marine layer was 1800 ft deep. The top of
the inversion was at 4000 ft with a temperature of 27 Celsius.

Fairly good confidence in TAFs. Flight Cat transition timing my
be off by +/- 1 hour. Flight cats may be 1 category lower than
fcst aft 01Z this evening.

KLAX...Fairly good confidence in TAF. There is a 20 percent chc
that cigs will remain blo OVC010 through the period. There is a
30 percent chc of 3SM OVC004 conds 11Z-15Z Friday morning. High
confidence that any east wind component will remain blo 6 kt.

KBUR...Fairly good confidence in TAF. VFR transition could occur
as late as 1930Z. There is a 30 percent chc of 2SM BR conds
10Z-12Z Friday morning.

&&

.MARINE...06/747 AM.

For the Outer Waters, moderate to high confidence in current
forecast. Today through Saturday, high confidence in winds and
seas remaining below Small Craft Advisory (SCA) levels. On Sunday,
there is a 30-40% chance of SCA level winds. On Monday, high
confidence in winds and seas remaining below SCA levels.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Today through Saturday, high
confidence in winds and seas remaining below SCA levels. For
Sunday, there is a 20-30% chance of SCA level winds in the
afternoon and evening hours. On Monday, high confidence in winds
and seas remaining below SCA levels.

For the Inner Waters south of Point Conception, high confidence in
current forecast. Today through Monday, winds and seas are
expected to remain below SCA levels.

Through the weekend, dense fog, with visibility of one mile or
less, will continue to impact the coastal waters north of Point
Conception during the night and morning hours.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory remains in effect until 8 PM PDT this evening
      for zones 38-343-344-379. (See LAXNPWLOX).
     Excessive Heat Warning remains in effect until 8 PM PDT this
      evening for zones 381>383. (See LAXNPWLOX).
PZ...NONE.

&&

$$

PUBLIC...Schoenfeld/Rorke/Cohen
AVIATION...Rorke
MARINE...RAT
SYNOPSIS...Smith/RS

weather.gov/losangeles

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