937
FXUS66 KLOX 092058
AFDLOX

Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
158 PM PDT Sun Jun 9 2024

.SYNOPSIS...09/120 PM.

Warmer temperatures are expected Monday through Wednesday as
onshore flow weakens in response to higher pressure moving into
the area. Most of the warming will be felt away from the coastal
areas where low clouds and fog will continue. After a brief
cooling trend Thursday widespread warmer temperatures are expected
Friday through next weekend with some gusty north winds at times.

&&

.SHORT TERM (TDY-WED)...09/142 PM.

A weak upper low continues to plague the area, resulting in a deep
and slow clearing marine layer south of Pt Conception and another
morning of drizzle. However, models continue to advertise the
upper low shifting to the southwest tonight and Monday and
Tuesday. We`re seeing signs of this today as gradients have been
trending weaker and the entire Central Coast has cleared out. As
the low pinches off and moves southwest tonight into Monday
onshore flow is expected to weaken further while warmer air aloft
lowers the marine layer depth to about half what it was this
morning. With these trends it`s unlikely (though not impossible)
that drizzle will repeat again Monday morning. Low clouds should
clear earlier and daytime highs will be warmer, especially
inland.

Tuesday expected to be the warmest of this mini heat wave with far
interior areas like the Antelope Valley getting into the lower
100s (though not as warm as last week) and warmer coastal valleys
near 90. Forecast highs were trimmed slightly as offshore trends
have lightened the last few runs but still enough for warming in
most areas. Still expecting low clouds and fog for coastal areas
but clearing earlier.

Models currently showing onshore flow increasing again Wednesday,
however, this may be a little premature as the a majority of the
ensembles show the upper low not starting to move back towards the
coast until early Thursday. So it`s possible that forecast highs
on Wednesday are too cool, especially inland.

.LONG TERM (THU-SUN)...09/157 PM.

Cooler weather on tap Thursday as the upper low moves across the
area from southwest to northeast. The low has very little moisture
associated with it so not expecting any afternoon showers or
storms in the mountains, but some increase in cumulus clouds there
is a good bet. Marine layer will be deepening as the lows treks
through, possibly enough for some more morning drizzle for
coast/valley areas.

A significant warming trend is expected Friday and Saturday as
heights rise and the air mass warms following the departure of the
upper low. At the same time onshore flow to the east weakens and
actually turns offshore to the north by around 3mb. The GFS is
showing around 50kt of north to northwest winds near and west of
Pt Conception, and 25-40 kt over the western Santa Ynez Range.
Will have to monitor this situation closely through the week as
these conditions could create some fire weather concerns.
Elsewhere, warmer valleys are expected to reach the 90s and
inland coastal areas expected to be in the mid 70s to lower 80s.

&&

.AVIATION...09/1643Z.

At 1630Z at KLAX, the marine layer was 2900 ft deep. The top of
the inversion was at 4800 ft with a temperature of 17 degrees C.

High confidence in 18Z desert TAFs.

Moderate confidence in 18Z coastal and valley TAFs. Timing of
flight category changes could be +/- 2 hours of current forecasts.
There is a 20-30% chance that coastal TAFs south of Point
Conception may not clear this afternoon.

KLAX...Moderate confidence in 18Z TAF. There is a 30% chance that
MVFR CIGs will not scatter out this afternoon. Timing of flight
category changes could be +/- 2 hours of current forecasts. There
is a 30% chance of IFR CIGs 05Z-16Z. No significant easterly wind
component is expected.

KBUR...Moderate confidence in 18Z TAF. Timing of flight category
changes could be +/- 2 hours of current forecasts.

&&

.MARINE...09/1205 PM.

For the Outer Waters, moderate to high confidence in current
forecast. For tonight, there is a 60-80% chance of Small Craft
Advisory (SCA) level winds. For Monday through Thursday, high
confidence in winds and seas remaining below SCA levels. On
Friday, there is a 50-70% chance of both SCA level winds and seas.
For the Inner Waters north of Point Sal, moderate to high
confidence in current forecast. There is a 50-60% chance of SCA
level winds this afternoon and evening. For Monday through
Thursday, high confidence in winds and seas remaining below SCA
levels. For Friday, there is a 40-50% chance of SCA level winds in
the afternoon and evening hours.

For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. For the western half of the Santa
Barbara Channel, there is a 30-40% chance of SCA level winds this
evening. Otherwise, high confidence in winds and seas remaining
below SCA levels through Friday for the Inner Waters south of
Point Conception.

&&

.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 Monday for
      zones 670-676. (See LAXMWWLOX).
     Small Craft Advisory in effect until 9 AM PDT Monday for zone
      673. (See LAXMWWLOX).

&&

$$

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