FXUS66 KLOX 280016 AAA

516 PM PDT Thu Apr 27 2017

...update for new aviation discussion...

A high pressure system with offshore flow will bring fair skies,
gusty winds at times and above normal temperatures into next week.
The weekend will have the warmest temperatures.



Gusty north to northwest flow pattern continues and we'll be
getting another surge tonight into Friday morning as a reinforcing
shot of upper level energy drops into the Great Basin. This could
be the strongest of the bunch this week (at least for LA County) as
models show solid 40-50 kt around 850mb and strong subsidence to
drive the stronger winds aloft down to the surface. So warnings
look good for the Grapevine area tonight and some of that will
filter down into the valleys and possibly even down into the LA
Coast as well.

Not too much change in temps Friday, but Saturday as we transition
to a solid advisory level Santa Ana event temps will definitely
jump several degrees, especially coast/valleys.

The Santa Ana is a one off event this time as Sunday we turn back
onshore and highs drop 4-8 degrees for coast/valleys (though
similar or slightly warmer farther inland).


Fairly quiet week next week as the ridge eventually moves squarely
over the west coast and dominates the pattern. Pretty standard
onshore flow each day so while above normal temps will continue
highs should mostly top out in the 70s for the coast and 80s for
the valleys. 90s likely reserved for the extreme inland areas like
the Antelope Valley and interior SLO County. This pattern is
definitely favorable for a marine lyr return at some point next
week, but exactly when is hard to say. When it does it will be
confined to the coast and likely include areas of dense fog as the
inversion will be very strong but also very shallow.



At 2317Z, The inversion at KLAX was 400 ft deep. The top of the
inversion was at 1000 ft with a temperature of 24 deg C.

Hi confidence in the 00Z TAFs with VFR conditions expected at all
the airfields thru Fri afternoon. Gusty nw to n winds will affect
many of the airfields for much of the TAF period. There will be an
extended period of low level wind shear at KSBA from 02Z-14Z due to
the gusty n canyon winds in the vicinity. Winds gusting to near 40
kt at KPMD and KWJF thru early this evening will bring a 10-20
percent chance of MVFR/IFR vsbys at times in blowing dust. At
KLAX...n winds gusting to 25 kt is expected later tonight into early
Fri morning.

KLAX...Hi confidence in the 00Z TAF with VFR conditions expected
thru Fri evening. N winds gusting to 25 kt is expected from 08Z-14Z,
with a 20 percent chance of gusts to 30 to 35 kt as well.

KBUR...Hi confidence in the 00Z TAF with VFR conditions expected
thru Fri afternoon. Gusty n winds will prevail at the airfield at
times, peaking tonight with gusts up to 25 kt, and there is a 20-30
percent chance of gusts 30 to 35 kt at times.


.MARINE...27/200 PM.

For the Outer Waters, high confidence in current forecast. Gale
force winds will continue through Friday night then subside to
Small Craft Advisory (SCA) levels Saturday through Monday.

For the Inner Waters, moderate to high confidence in current
forecast. For the waters north of Point Sal, SCA level winds will
continue through Friday night before subsiding on Saturday.
However for Sunday and Monday, there is a 60% chance of winds
increasing to SCA levels again. For the waters south of Point
Conception, SCA level west to northwest winds will continue
through Friday night. From Saturday through Monday, winds are
generally expected to remain below SCA levels. However, there is a
50% chance of SCA level northeast winds Saturday from Ventura
south to Santa Monica.

Due to strong winds throughout the waters, seas will be very
choppy in all areas this week, making for hazardous boating
conditions through the week.


CA...Wind Advisory in effect until 9 PM PDT this evening for zones
34-35. (See LAXNPWLOX).
Wind Advisory in effect until 9 AM PDT Friday for zones
39-44>46-52-59-547. (See LAXNPWLOX).
Beach Hazards Statement in effect through Friday evening for
zones 40-41. (See LAXCFWLOX).
High Wind Warning in effect until 9 AM PDT Friday for zones
53-54. (See LAXNPWLOX).
Wind Advisory in effect until 3 PM PDT Friday for zone 88. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 AM PDT Saturday for
zones 645-650-655. (See LAXMWWLOX).
Gale Warning in effect until 3 AM PDT Saturday for zones
670-673-676. (See LAXMWWLOX).


No significant hazards expected.




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