Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 08/08/20

Area Forecast Discussion

National Weather Service Los Angeles/Oxnard CA

 805 PM PDT Fri Aug 7 2020

.SYNOPSIS...07/738 PM.

Overnight and morning low clouds and fog with below normal
temperatures will continue across the coasts and in adjacent
valleys into next week. Interior areas will warm to near normal
Sunday through Tuesday then little change through Thursday.

&&

.SHORT TERM (FRI-MON)...07/805 PM.

A very weak upper level low will spin over north-central
California through Saturday, then get nudged to the west Sunday
and Monday by a building high over northern Mexico. This will
bring warming to the mountains and interior valleys over the
weekend, pushing temperatures back up to around normal for this
time of the year by Sunday and Monday. This includes daytime
temperatures well into the 90s across the warmest valleys and
lower mountains, as well as temperatures approaching 100 degrees
in the Antelope Valley.

Meanwhile, the coastal plain and coastal valleys will continue to
be moderated by a marine layer influence and steady onshore flow.
The marine layer depth is ranging from around 1500 feet across
the LA Basin (according to ACARS data) and around 2000 feet north
of Pt Conception (according to 00z Vandenberg sounding). With the
gradual rise in heights over the weekend, look for the marine
layer depth to gradually diminish leading to the warming trend
across inland areas. Overnight into Saturday morning, expecting
low clouds to fill in across many coastal areas as well as
portions of the coastal valleys.

Continued gusty onshore winds across the interior through Monday,
especially across the Antelope Valley and adjacent foothills where
wind gusts of 25 to 35 mph will be common, except isolated gusts
of 40 to 45 mph near Lake Palmdale. The gusty onshore winds
coupled with the warming temperatures and lowering humidities will
result in elevated fire weather concerns this weekend into Monday
across the Antelope Valley and adjacent foothills. There are
also some localized northwest winds gusting 25 to 35 mph this
evening near Gaviota and Refugio, which will diminish over the
weekend.

.LONG TERM (TUE-FRI)...07/210 PM.

Tuesday is looking very similar to Monday, with the upper level high
centered over northern Mexico still supporting near normal
conditions over the interior, while modest onshore flow drives
slightly cooler than normal conditions at the coast. Computer
projections differ for Wednesday and Thursday, along with a decent
spread in their ensembles, between the ridge flatten out with a
cooling trend and the ridge expanding with a warming trend. There
is more agreement for Friday into the following weekend, with
good consensus towards a widespread and gradual warming trend.
Also expecting northwest winds to reform over SBA County by
Tuesday or Wednesday nights, which should help deepen the marine
layer over LA County, and decrease it over SBA and Ventura
Counties. No appreciable threat of any monsoonal surge or
significant winds for the next 7 to 10 days.

&&

.AVIATION...08/0007Z.

At 2355z at KLAX... The inversion was around 1500 feet. The top
of the inversion was around 2900 feet with a temperature of about
21 degrees Celsius.

Overall... Moderate to high confidence in the current TAFs.
VLIFR/LIFR conditions will likely develop at KSBP and KSMX
tonight into early Saturday morning. LIFR/IFR conditions likely
to develop at KPRB, KSBA, KOXR, and KCMA 12z-17z, IFR/MVFR
conditions at KSMO, KLAX, and KLGB 11z-18z. There is a 20 percent
chance of IFR/MVFR conditions developing at KBUR and KVNY 12z-
17z. Otherwise and elsewhere, VFR conditions will prevail.

KLAX... Moderate confidence in the current TAF. IFR/MVFR conditions
are projected to develop 12z-17z, however there is a 20 percent
chance of no cigs developing. Otherwise, VFR conditions will
prevail throughout the forecast period. There will not be any east
winds greater than 8 kts.

KBUR... High confidence in the current TAF. There is a 20 percent
chance of IFR/MVFR conditions 12z-17z. Otherwise, VFR conditions
will prevail throughout the forecast period.

&&

.MARINE...07/731 PM.

Across the outer waters... Winds across the central and southern
outer waters will be elevated and gusty to Small Craft Advisory
(SCA) level through late tonight. Otherwise, conditions will
remain below SCA level throughout the forecast period.

Across the nearshore waters of the Central Coast... Conditions
will remain below SCA level throughout the forecast period.

Across the inner waters south of Point Conception... Conditions
will remain below SCA level throughout the forecast period.

Patchy fog, locally dense with visibility under one mile, will
continue through the weekend. The lowest visibility and most
widely spread conditions will occur in the overnight and morning
hours.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Saturday for
      zones 673-676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK (MON-FRI).

No significant hazards expected.

&&

$$

PUBLIC...Gomberg/Kittell
AVIATION...Gomberg
MARINE...Kj
SYNOPSIS...Kj

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