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fxus66 klox 251142 
afdlox

Area forecast discussion
National Weather Service Los Angeles/Oxnard California
341 am PST Sat Feb 25 2017

Synopsis...
dry and cool conditions will continue today. A couple of weak
weather systems will bring and a good chance of rain and mountain
snow tonight and early Sunday, with a chance of showers continuing
through Monday. High pressure will bring clear skies and a warning
trend to the region Tuesday through Wednesday, with above normal
temperatures expected Thursday and Friday

&&

Short term...(tdy-mon)

Clear skies across the forecast area this evening, although an
area of clouds was approaching the central coast. A compact
but moderately energetic upper low was located off the coast of
far northern California early this morning. This system is
forecast to drop southward today, opening up into a positively
tilted trough as it moves through the San Francisco Bay area
today. Ahead of this system, clouds will increase across the
region today, especially across slo and sba counties where it
should become mostly cloudy in the afternoon. It will be another
chilly day across the forecast area, with temps 5 to 10 degrees
below normal once again.

Due to the compact nature of this system, its exact track will be
critical in determining where it brings rain to the region. At
this point, all models favor it likely bringing a period of rain
to slo and sba counties tonight, with light rain likely late
tonight across vtu County and at least western Los Angeles County.
There is just a chance of rain across eastern Los Angeles County.
There will be a lingering chance of rain across vtu and l.A.
Counties early Sunday morning.

As this system moves into the forecast area, it is forecast to
really minor out and weaken, so mid level dynamics will be on the
decrease. Therefore, expect any rainfall totals to be on the light
side, generally one quarter to one half inch across slo and sba
counties, with locally higher totals in the mountains, and one
tenth to perhaps one third of an inch across vtu and western l.A.
County. There will likely be some breaks of sunshine across the
area Sunday afternoon. Lingering moisture and instability due to
fairly cold air aloft will keep at least a slight chance of
showers across the region Sunday afternoon and evening. Snow
levels will be rather low, down to between 4000 and 4500 feet late
tonight and early Sunday. While snow accumulations should
generally be on the order of 1 to 3 inches or maybe slightly
higher, there is a chance that snow could affect travel on
portions of Interstate 5 near the Grapevine tonight/Sunday
morning.

This system will zip to the east of the region Sunday afternoon.
A broad trough will drop southward across California Sunday night
and Monday. An organized area of fairly decent rain is expected
to develop in within a plume of subtropical moisture by late
Monday, but this will be aimed well to the south of the region,
across northern baja. Otherwise, there should be enough moisture
for at least a few showers across the region Sunday night and
Monday, but probably just Worth slight chance pops in most areas.
It will remain cool across the region on Monday.

Long term...(tue-fri)

The broad trough will move east of the region on Tue, with a
northwesterly flow pattern aloft setting up over the forecast
area. A very weak upper impulse will ripple through the area on
Tue. Skies should be partly cloudy, but it will remain cool
across the region thanks to low heights and thicknesses. Heights
will rise across the region Wed through Fri as an upper ridge
develops over the eastern Pacific. There may also be some
offshore across the region Thu and Fri. Expect warming to begin on
Wed, with temps up to near normal levels, then more significant
warming is expected Thu and Fri, with high temps possibly reach 80
degrees in some inland coastal and valley areas.

&&

Aviation...26/1100z...

At 1050z, there was no marine inversion at klax.

Overall, moderate to high confidence in current forecast. High
confidence in VFR conditions through this evening. Overnight,
moderate confidence in VFR conditions (as there is a 40% chance of
MVFR cigs developing as storm approaches).

Klax...moderate confidence in 12z taf. High confidence in VFR
conditions through this evening and moderate confidence overnight
(as there is a 30% chance of MVFR cigs developing after 10z).
Additionally, light rain will be possible after 10z.

Kbur...moderate confidence in 12z taf. High confidence in VFR
conditions through this evening and moderate confidence overnight
(as there is a 30% chance of MVFR cigs developing after 10z).
Additionally, light rain will be possible after 10z.

&&

Marine...25/130 am...

For the outer waters, high confidence in current forecast. Through
Wednesday morning, winds and seas are expected to remain below
Small Craft Advisory (sca) levels (although there is a 20% chance
of gusts reaching Small Craft Advisory levels this afternoon/evening). By Wednesday
afternoon and evening, winds will strengthen with a chance of Small Craft Advisory
level winds developing.

For the inner waters, high confidence in current forecast. Winds
and seas are expected to remain below Small Craft Advisory levels through Wednesday
for all the inner waters.

&&

Lox watches/warnings/advisories...
California...none.
Pz...none.

&&

Hazard potential outlook...(mon-fri)
no significant hazards expected.

&&

$$

Public...db
aviation...Thompson

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