055
FXUS66 KLOX 102108
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
208 PM PDT Mon Jun 10 2024

.SYNOPSIS...10/104 PM.

Temperatures Tuesday are expected to warm a few more degrees as
high pressure builds and onshore flow weakens. Cooler temperatures
are expected Wednesday and Thursday as an upper low moves through
causing the marine layer to deepen. Then turning warmer again
Friday through the weekend with locally gusty northerly winds.

&&

.SHORT TERM (TDY-THU)...10/131 PM.

Significant warming started today as onshore flow weakened in
response to building high pressure aloft. At 1pm most of the
valleys and other interior areas were 10-15 degrees warmer than
yesterday at this time. Meanwhile, at the coast temperatures were
about the same as yesterday with slow clearing of low clouds and
fog and a chilly sea breeze. High pressure will peak tomorrow
while onshore gradients will be at their weakest, pushing the
marine depth down to around 1500 feet and leading 4-8 degrees of
additional warming across inland areas. Low clouds may still sneak
into the coastal valleys later tonight but will clear off quickly.
Closer to the coast low clouds may still linger into the
afternoon in some areas.

Models remain consistent indicating increasing onshore flow
Wednesday as the upper low to our southwest starts to move back
towards the coast. There is still some uncertainty how much
cooling will happen Wednesday but most of the ensemble solutions
show 2-4 degrees of cooling across inland areas and little change
at the coast. More significant cooling Thursday as the upper low
is overhead and onshore gradients to the east bounce back up to
around 10mb in the afternoon. The marine layer will increase to
around 3000 feet again with some morning drizzle possible across
coast and valleys.

.LONG TERM (FRI-MON)...10/207 PM.

The upper low will move quickly through the area Thursday with
building heights Friday and Saturday and weakening onshore flow.
Models have been consistent showing a significant increase in
northerly flow across the western portion of forecast area. Models
weren`t quite as warm today as they have been the last few days
but forecast 950mb winds have increased to 50-60kt just west of Pt
Conception and northerly gradients have jumped to almost 5mb,
peaking early next week at close to 6mb. Humidities will be
dropping across the interior as well as portions of the Santa
Barbara south coast as the Sundowner winds funnel through the
passes and canyons. Winds will be increasing across the northern
LA/Ventura mountains as well but models are definitely focusing on
southern Santa Barbara County for the strongest winds.

Temperatures will be warming up Friday/Saturday and this time
coastal areas will see some of the warming as well, especially in
southern SB County. With the northerly flow in place any marine
layer clouds will be confined to LA and Ventura Counties at most,
and it`s possible it will get pushed south of LA County. Highs
expected to reach the lower 80s across inland parts of the coastal
plain and low to mid 90s in the warmer coastal valleys.

Strong northerly flow will continue across the western areas
into early next week maintaining elevated fire concerns there.
Models show a coastal eddy developing Sunday into Monday that
would increase marine layer for LA/Ventura Counties and cool
temperatures at least a few degrees.

&&

.AVIATION...10/1731Z.

At 1656Z at KLAX, the marine layer was 2300 ft deep. The top of
the inversion was at 3900 ft with a temperature of 19 degrees C.

For the 18Z TAF package, high confidence in desert TAFs and
moderate confidence in coastal and valley TAFs. Lower confidence
for coastal and valley sites due to uncertainties in marine layer.
Timing of flight category changes could be +/- 3 hours of current
forecasts.

KLAX...Moderate confidence in 18Z TAF. Timing of flight category
changes could be +/- 3 hours of current forecasts. Also, there is
a 20% chance of LIFR conditions 08Z-14Z time frame. No significant
easterly wind component is expected.

KBUR...Moderate confidence in 18Z TAF. Timing of flight category
changes could be +/- 3 hours of current forecasts. Also, there is
a 20% chance of LIFR conditions 08Z-14Z time frame.

&&

.MARINE...10/1226 PM.

For the Outer Waters, moderate to high confidence in current
forecast. Tonight through Thursday, high confidence in winds and
seas remaining below Small Craft Advisory (SCA) levels. For Friday
and Saturday, high confidence in combination of SCA level winds
and seas with a 20-30% chance of Gale force winds on Saturday.

For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. Tonight through Thursday, high
confidence in winds and seas remaining below SCA levels. For
Friday and Saturday, high confidence in SCA level winds,
especially in the afternoon and evening hours. On Saturday, there
is a 10-20% of Gale force winds.

For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. Tonight through Thursday, high
confidence in winds and seas remaining below SCA levels. On
Friday and Saturday, there is a 50-60% chance of SCA level winds
across the western half of the Santa Barbara Channel with high
confidence in winds and seas remaining below SCA levels elsewhere.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...MW
AVIATION...RAT
MARINE...RAT
SYNOPSIS...MW

weather.gov/losangeles

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