Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 07/09/19

Area Forecast Discussion

National Weather Service Los Angeles/Oxnard CA

 818 PM PDT Mon Jul 8 2019

.SYNOPSIS...08/1149 AM.

Morning clouds will give way to afternoon sunshine, with the
exception of a few beaches that will remain cloudy. Throughout the
week, afternoon temperatures will rise and overnight and morning
clouds will diminish each day.

&&

.SHORT TERM (MON-THU)...08/817 PM.

Weak upper level trough over the region will gradually lift
northward as upper level high pressure system begins to expand
northwestward towards southeast California on Tuesday afternoon.
This will result in higher heights returning to the region
on Tuesday, with a corresponding shrinkage of the marine layer.
Earlier this morning, the marine layer had deepened to
around 3500 feet, but current ACARS data and 00z Vandenberg
sounding showing the marine layer depth ranging between 2000
and 2500 feet. Current satellite imagery showing patches of
low clouds returning to some coastal areas this evening, with
low clouds expected to fill in across many coastal/valley
areas overnight into Tuesday morning.

Afternoon high temperatures are expected to rise 3 to 5 degrees
across most interior areas, still slightly below normal for this
time of year. As heights/thicknesses build Wednesday into
Thursday, warming trend will be more noticeable across interior
sections, with highs climbing back into the 90s in the warmest
valleys, and reaching around 100 degrees in the deserts.

*** From previous discussion ***

As for winds, no major issues expected. The decreasing onshore
gradients will result in weaker southwesterly winds each afternoon
and evening across interior sections. With the strengthening
northerly offshore gradients, some locally gusty northerly winds
can be expected each night through and below the Santa Ynez Range
with the strongest winds from Refugio westward. Overall, expect
wind speeds to remain below advisory levels.

.LONG TERM (FRI-MON)...08/202 PM.

For the extended, 12Z models continue in good agreement,
indicating very July-like weather for the district. Main feature
will be the development of the 4-Corners high over the desert
Southwest and the continued weak surface gradients.

With the 4-Corners high and weak gradients, the marine inversion
will remain shallow with limited stratus/fog during the night and
morning hours. Any stratus that develops could remain rather
stubborn along the beaches due to the atmospheric subsidence
strengthening the marine inversion. With respect to temperatures,
expect rather warm temperatures for all areas with Friday and
Saturday likely the warmest days with most areas 4-8 degrees above
seasonal normals.

At this time, models do not indicate much, if any, surge of
monsoonal moisture at this time. However, given the location of
the ridge, the possibility of some monsoonal moisture moving into
the area during the period needs to monitored closely each day.

&&

.AVIATION...08/2338Z.

At 2335Z, the marine layer depth was near 3000 feet deep at KLAX.
The top of the inversion was around 4800 feet with a temperature
near 19 degrees Celsius.

Moderate confidence in the current forecast.

For areas north of Point Conception, IFR/LIFR cigs expected
to prevail tonight into Tuesday morning. For areas south of
Point Conception, expecting mostly IFR/MVFR cigs tonight into
Tuesday morning, but have delayed some of the arrival times
of cigs in latest TAF package based on latest satellite/model
trends. Some low clouds could linger near immediate coastal
areas into the afternoon hours on Tuesday.

KLAX...Moderate confidence in the 00z TAF. Expecting arrival
time of MVFR cigs between 04z-06z and likely persisting through
Tuesday morning, with a 20 percent chance of cigs lingering into
the afternoon hours.

KBUR...Moderate confidence in the 00z TAF. Have delayed arrival
time of MVFR cigs at KBUR to 11z, with earlier burnoff time
expected on Tuesday morning. There is a 30 percent chance of
IFR cigs at KBUR early Tuesday morning.

&&

.MARINE...08/817 PM.

Moderate to high confidence in the current forecast.

For the Outer Waters, Small Craft Advisory (SCA) level winds
are expected across the two northern zones through late tonight.
Winds will diminish some on Tuesday, with a 50 percent chance of
SCA level winds across all the Outer Waters Tuesday night
increasing to a 70 percent chance Wednesday through Saturday.

For the Inner Waters north of Point Sal, winds and seas should
remain below SCA levels through Wednesday afternoon. There is a 50
percent chance of SCA level winds Wednesday evening increasing to
a 60 percent chance of SCA conditions Thursday afternoon through
Friday.

For the Inner Waters south of Point Conception, winds and seas
are expected to remain below SCA levels through Wednesday
afternoon. By Wednesday evening, SCA level winds are likely over
the western SBA Channel during the late afternoon to evening
hours through Friday, and possibly through Saturday.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Tuesday for
      zones 670-673. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK (THU-MON).

No significant hazards expected.

&&

$$

PUBLIC...Gomberg/Thompson
AVIATION...Gomberg
MARINE...Smith
SYNOPSIS...AA

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