Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 291111
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
411 AM PDT FRI JUL 29 2016

.SYNOPSIS...
High pressure aloft will result in above normal temperatures
through Saturday, with night through morning low clouds and fog
affecting some coastal areas. Weakening high pressure will bring
high temperatures back to near normal levels Sunday, with only
minor changes in high temperatures expected through mid week.
Monsoonal moisture will bring a slight chance of thunderstorms
to the mountains and desert early next week.

&&

.SHORT TERM...(TDY-SUN)

Low cloud pattern was very similar to this time on Thu, with clouds
widespread on Central Coast, pushing locally into the Santa Ynez Valley.
With a shallow marine layer in place, there was some locally dense fog,
but too localized to require dense fog advisories. Some patches of stratus
were also developing in the coastal waters south of Pt Conception, and
should push into coastal sections of srn SBA County and VTU/L.A. Counties
by daybreak, but only into locations near the immediate coast.
Once again, all low clouds should be gone by mid morning. With slightly
weaker onshore flow, max temps may be up a couple of degrees west of
the mtns, with only minor changes in the mtns and the Antelope Valley.
This should put high temps in the warmer valley locations close to
105 degrees, with highs approaching 110 degrees in the warmest locations
in the Antelope Valley. That would be close to Excessive Heat Warning
levels, but dew points should be low enough to keep heat index values
below thresholds. There may be a few buildups in the mtns and across
eastern sections of the Antelope Valley today, but do not expect any
showers/thunderstorms.

The upper high over northern AZ and southern NV will slowly weaken
tonight thru Sunday. This should bring a few degrees of cooling each
day, bringing temps back to near normal levels in most areas by Sunday.
Night through morning low clouds may become a bit more widespread in
coastal areas tonight and even more so Saturday night, but the marine
layer should remain shallow enough so that most valley locations will
remain mostly clear. The exception to this will likely be the Santa
Ynez Valley, and possibly lower portions of the San Gabriel Valley.
There will be some mid and high levels moisture, particularly across
eastern sections of the forecast area over the weekend, but at this
point, expect just some buildups each afternoon and evening.



.LONG TERM...(MON-THU)

The upper high will linger over Nevada into Tuesday, then it
will be forecast westward off the coast as a trough moves thru
the Pac Nw Tue through Wed. The upper flow and moisture profile
look to be favorable for a slight chance of showers/tstms in the
mtns and Antelope Valley Mon and possibly Tue, then less so
thereafter. Expect minor day to day fluctuations in the night
through morning low cloud patter, generally confined to the
coastal plain, with max temps generally near normal thru the pd.


&&

.AVIATION...29/1100Z.

At 1030z, the marine layer was around 1000 feet deep at KLAX. The
top of the inversion was near 4300 feet with a temperature around
30 degrees celsius.

N of Point Conception...Moderate confidence with 12z tafs.
Will continue to with persistence with little changes expected
over the next couple of days. Cigs should remain LIFR/IFR. Expect
similar timing for cigs to scour out and redevelop tonight into
Sat morning.

S of Point Conception...Low confidence with 12z tafs for coastal
tafs. At this point looks like cigs will stay off the coast
allowing VFR conds. But there could be a late surge into the
LA/VTU/SBA coastal sites after 12z. Just not very confident.
Expect a similar type of pattern tonight into Saturday with low
confidence in coverage and timing of IFR cigs.

KLAX...Low confidence with return of IFR cigs between 12Z and
16Z. There is a 40 percent chance that VFR conditions could
persist through entire 24 hour forecast period.

KBUR...High confidence in VFR conditions through period.

&&

.MARINE...29/300 AM.

High confidence with the forecast through this weekend. Have
taken down the Small Craft Advisory for This afternoon for Zone
PZZ673 through early Saturday morning mainly affecting coastal
areas around Point Conception. Mainly because only expecting
local gusts to 25 kt around that region. There is a 40% chance
that gusts could become more widespread and the SCA might need to
be added late this afternoon. Otherwise no significant issues
across the coastal waters through this weekend.

A small but long period southerly swell will develop Saturday
night through Sunday. Not anticipating any issues.


&&

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

&&

$$

PUBLIC...DB
AVIATION...CK
MARINE...CK
SYNOPSIS...DB

weather.gov/losangeles


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