Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 261048

348 AM PDT Fri May 26 2017

A deep moist layer with strong onshore flow will continue to
bring plenty of clouds across much of the forecast area through
Saturday. Gusty winds across the Antelope Valley will continue
through this evening. An upper ridge will build in for a couple
days late this weekend into early next week allowing for a brief
warm up and less cloud coverage...especially inland. Another area
of low pressure will move into Southern Cal by mid week bringing
more cool weather through the end of the week.



Marine Layer is up to 5000 feet. Too high for drizzle over the
flatter terrain and was removed from the coastal and marine
sections. The upper trof that was forecast to provide enough lift
for more drizzle or a shower or two really look too far east and
too weak to do much of anything over CA. Still with the onshore
push (+9.5 to KDAG) there is a slight chance that some moisture
will be wrung out of the marine layer near the foothills and the
coastal slopes. Today looks like a textbook case for reverse
clearing and expect the coasts to have good clearing during the
afternoon while the vlys remain cloudy. Max temps will remain
below normal but will be a degree or two warmer than ydy as hgts
will rise...the onshore flow will be a slosh weaker and there will
be a little more sunshine. 10 mb onshore flow is more than enough
to keep the advisory level winds going over the Antelope Vly esp
in the western foothills.

A slight ridge builds in for Saturday and onshore flow will weaken
to moderate levels. The marine layer will be disorganized and the
stratus formation will be a little more haphazard but most of the
coasts and vlys will likely have low (maybe lower is the better
word) clouds by sun up. There will be much better clearing and max
temps will bump up 3 to 6 degree but will remain blo normal.

Sun and Mon are shaping up to be a pair of nice days with a 52 DM
ridge in place. The biggest jump in temps will occur on Sunday
with 8 to 12 degrees of warming likely. Monday will be the warmest
day of the next 7 with another 1 to 2 degrees of warming. Max
temps will be 4 to 8 degrees warmer than normal on Monday. A
typical for this time of year night through morning low cloud
pattern will continue but there will be total clearing by mid to
late morning each day as the onshore push relaxes.


The EC and the GFS have changed their tune from last nights
forecast and neither forecast a cut off low. Both advertise a
slowly developing weak trof and increasing onshore flow. The
marine layer will increase in coverage and duration. Hgts will
slowly lower. Max temps will cool each day and will dip below
normal on Wednesday.



At 1000Z, the marine inversion at KLAX was around 5000 feet deep.
The top of the inversion was 7400 feet with a temperature of 13
degrees Celsius.

Moderate confidence for VFR or high MVFR cigs through the next 24
hours. A deep moist layer will persist over the region. 50% chance
for morning drizzle or isolated light rain in the valleys and
foothills of LA/VTU valleys. Vsbys could become IFR in those
conditions. 30% chance for -DZ for coastal areas of LA/VTU through
15z this morning. Low to moderate confidence that clearing along
the coast will occur after 20z while inland TAF sites remain
mostly cloudy. There is a 20% chance that the deep moist layer
could collapse altogether late this afternoon into this evening
and be slow in reorganizing across coast and valleys to coastal
slopes tonight into Sat morning.

KLAX and KBUR...VFR or high MVFR cigs will persist over the next
24 hours. 50% chance that cigs could across LAX could persist
after 20Z today. Higher confidence that KBUR will remain cloudy
all day. Not anticipating any easterly wind issues for KLAX over
the 30 hours.


.MARINE...26/230 AM.

No real issues across the coastal waters through Saturday morning.
60 % chance for SCA level gusts to develop across the outer
waters by Saturday afternoon and continue into early next week.
Higher confidence for SCA level gusts by Sunday afternoon through
Monday morning. A GALE WATCH might be needed for the western
portion of the outer waters as far south as just west of the
Channel Islands through at least the middle of next week. 50%
chance. Local SCA gusts possible across the western portion of the
SBA Channel inner waters Mon through Wed.


CA...Wind Advisory in effect until 9 PM PDT this evening for zone
      59. (See LAXNPWLOX).


No significant hazards expected.



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