Southwest California area forecast discussion
National Weather Service Los Angeles/Oxnard California
915 am PDT Sat may 18 2013
Synopsis...
A developing ridge of high pressure will bring a warming trend to
the area through Monday. A tightening northerly pressure difference
across the area will bring gusty north winds to portions of the area
mountains...southern Santa Barbara County and the Antelope Valley
through the weekend. A cooling trend is expected for the middle and
end of next week as a trough approaches the area.
&&
Short term (today-mon)...another day of breezy northwest winds in
the same areas, central coast, southern sba County, i5 corridor, and
Antelope Valley. Winds will be close to advisory levels in all those
areas. Inversion remains weak and marine layer clouds were spotty at
best. Gradients trending a mb or so offshore so with all else being
pretty much the same most inland areas should see temperatures a couple
degrees warmer than Friday.
Ridge builds in tonight through Monday, with Monday being the
warmest day. Monday morning a decent little northeast push sets up
mainly for the Ventura/la mountains. But the combination of that and
the ridge will be enough to push temperatures up into the 90s for the
warmer valleys. Marine layer should become a little more solid as the
inversion strengthens, but coverage likely to be confined to la
County coast.
***From previous discussion***
Long term (tue-fri)...
all extend models in good agreement for the long term and nothing has
changed from the previous forecast thinking. A large cool upper low will
move into the Pacific northwest Tuesday then settle over Oregon and then spin
through the period. Tuesday will be a transition day with a growing
marine layer and cooler but still above normal temperatures. By
Wednesday the onshore flow and cyclonic flow will combine to drive
the low clouds into the valleys. Coastal clearing will be slow and
some beaches will likely stay cloudy. Maximum temperatures will drop to below
normals across the coast and valleys but will be near normal inland.
&&
Aviation...
18/1140z
Areas of stratus will linger through middle to late morning across l.A.
County and portions of vtu County...with conds mostly MVFR.
North of pt Conception...stratus with generally IFR conds will affect
the Santa Ynez Valley and southern sections of the central coast
through middle or late morning. Expect marine layer to become more
shallow tonight...with stratus likely confined to coastal sections
of l.A. County and portions of the central coast.
Gusty north winds through and below passes and canyons of the Santa Ynez
range late this afternoon through late tonight will cause some low level wind shear
and MDT to strong uddf in the vicinity of ksba.
Klax...moderate confidence in 12z taf. There is a 20 percent chance
that conds will remain VFR this morning. There is a 20 percent
chance that ceilings will arrive as late as 12z tonight.
Kbur...high confidence in 12z taf. There is a 20 percent chance that
ceilings will linger through 18z.
&&
Lox watches/warnings/advisories...
Wind Advisory (see laxnpwlox).
Small Craft Advisory (see laxmwwlox).
Gale Warning (see laxmwwlox).
&&
$$
Public...mw/rorke
aviation...db
synopsis...Sweet
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