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Area forecast discussion 
National Weather Service Los Angeles/Oxnard California
1003 PM PST sun Feb 7 2016

..aviation discussion updated...

Synopsis...

High pressure and gusty offshore winds will bring well above
normal temperatures with possible record temperatures through
early next week. The high will weaken towards the end of the week
for a cooling trend...however temperatures will remain above
normal.

&&

Short term...(sun-wed)

Skies were Crystal clear this afternoon with moderate Santa winds
occurring across the usual wind prone areas. By this
evening...winds will increase in response to a strong surface high
strengthening over the Great Basin. This will cause a tight
surface gradient to set up over Southern California. Latest NAM-
WRF surface gradient between lax-dag is around -9mb for 12z or (4am
pst) Monday morning. This will be mainly a gradient driven wind event
from this evening through Monday. High wind warnings are in effect
for the mountains of Los Angeles and Ventura counties including
the Santa Monica range. Also included is the Santa Clarita valley
and a portion of the Ventura valleys including Simi Valley...to
Newbury Park and cities in between...including Westlake
Village...Thousand Oaks and Moorpark. Expect sustained winds
between 25 and 40 miles per hour with gusts ranging between 60 and 70 miles per hour.
Peak wind gusts will be late tonight into Monday morning.
Otherwise wind advisories will continue to be in effect for the
usual wind prone areas of Los Angeles and Ventura counties. Highs
today are expected to reach the lower to middle 80s today.

A red flag warning is also in effect for Los Angeles and Ventura
counties...excluding the Antelope Valley from 6 PM this evening
through Monday evening at 6 PM. This is due to to the strong winds and
low relative humidity. See the fire discussion below for more
details.

Synoptically...a high amplitude ridge will persist over the
western states into the Pacific northwest through Tuesday. The ridge axis
will then shift eastward. There will continue to be a weaker ridge
of Southern California while northern California has an upper
trough moving towards the state. This will keep much of the
atmosphere warm overhead. Throw in persistent moderate offshore
winds through Tuesday and high temperatures will reach the middle to upper
80s Monday-Tuesday with a few coast and valley locations possibly
reaching 90 degrees. High temperatures will be a bit cooler across the
interior but still remain above normal for this time of year.
There could be a few heat records broken or tied including
downtown Los Angeles...ucla and Paso Robles on Monday...with more
widespread records possibly on Tuesday including downtown l.A.
Once again.

By Tuesday night into Wednesday...a shortwave ridge will briefly
strengthen over much of California just ahead of the trough.
Although heights will be slightly higher...onshore flow is
expected to kick in by late Wednesday due to the proximity of the
upper trough closer to the forecast area. Best cooling will occur
across the coastal areas...with less cooling for inland areas.
Expect 4 to 8 degrees of cooling along the coast with a couple of
degrees cooling expected for inland areas. Skies should remain
mostly clear during the short period forecast.




Long term...(thu-sun)

Both the GFS and European model (ecmwf) are in good agreement that the upper ridge
will finally break down as an upper trough approaches. There will
continue to be a modest cooling trend with highs only reaching the
upper 70s by Friday. The main trough axis will move over the
forecast area on Sat/sun but will remain dry...but cooler overall. However
still above normal for this time of year. Models continue to keep
Southern California dry into at least middle February.



&&

Aviation...08/06z.

At 04z at klax... there was no notable inversion.

Overall... high confidence in the 06z tafs. VFR conditions will
prevail throughout the forecast period. There is a thirty percent
chance of low-level wind shear and turbulence at terminals south
of Point Conception.

Klax... high confidence in the 06z taf. VFR conditions will
prevail throughout the forecast period. There is a twenty percent
chance of low-level wind shear and turbulence. Any east winds will
remain 7 knots or less.

Kbur... high confidence in the 06z taf. VFR conditions will
prevail throughout the forecast period. There is a thirty percent
chance of low-level wind shear and turbulence.

&&

Marine...06/200 PM...

There is a chance northeast winds will redevelop Sunday morning
and there is a chance the area will include Ventura Harbor and
extend out to the northern Channel Islands. There is a chance that
the northeast winds will increase early Monday morning and gale
gusts will exist from sunrise to midday Monday from Ventura Harbor
to Santa Monica and out to the northern Channel Islands.




&&

Fire...07/200 PM...

No changes to previous thinking...as red flag warnings will remain
in effect for Ventura County and Los Angeles County (except for
the Antelope valley) from 600 PM this evening through 600 PM
Monday evening. Strong northeast winds along with low relative
humidity will generate critical fire weather conditions through
Monday afternoon.

For Monday night and Tuesday...the offshore winds will be
weaker...but it will still be very warm and dry. So...there will
continue to be an elevated fire weather risk...and even a chance
that critical fire weather conditions may continue across sections
of Ventura and Los Angeles counties.



&&

Lox watches/warnings/advisories...
California...red flag warning in effect until 6 PM PST Monday for zones
40-41-44>46-53-54-547-548. (See laxmwwlox).
Wind Advisory in effect until 2 PM PST Monday for zones
40-41-44-547-548. (See laxmwwlox).
High Wind Warning in effect until 2 PM PST Monday for zones
45-46-53-54. (See laxmwwlox).
Pz...Small Craft Advisory in effect until 3 PM PST Monday for
zones 650-655. (See laxmwwlox).
Small Craft Advisory in effect until noon PST Monday for zone
676. (See laxmwwlox).

&&
$$

Public...gomberg
fire...gomberg
aviation...kj
marine...Smith
synopsis...Hall

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