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fxus66 kmtr 271450 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
750 am PDT Mon Mar 27 2017

Synopsis...partly cloudy skies are forecast today along with
brisk northwest winds during the afternoon and evening. High
pressure will build over California through midweek, resulting in
dry weather and a warming trend through Wednesday. Slightly cooler
conditions are expected on Thursday as a weather system moves
into eastern California. That weather system will bring only a
slight chance of showers to the northern and eastern portions of
our area, and also result in blustery conditions near the coast
and in the hills by late Thursday. High pressure will redevelop
late in the week and result in warmer weather once again by the
weekend.

&&

Discussion...as of 7:45 am PDT Monday...kmux shows that the last
few showers this morning have finally dissipated. Overall looks
very quiet for our weather today outside of breezy northwesterly
winds especially along the coast. Highs will mostly be in the 50s
to mid 60s. 12z NAM now in through Thursday continues to downplay
precipitation chances from the mid-week inside slider.

No major updates planned.

Previous discussion...the weak frontal system that brought
light rain to much of our region Sunday afternoon and evening has
moved off to our east and south early this morning. Radar still
shows isolated light showers over our area, but all shower
activity is expected to end by daybreak as drier air continues to
move in from the northwest. That drier airmass is already
resulting in clearing in the North Bay and this clearing trend is
expected to continue from north to south through this morning. By
afternoon, expect mostly sunny to partly cloudy skies in all
areas.

Surface high pressure will begin to build off the northern
California coast today and the resulting tightening pressure
gradients will generate brisk northwest winds along the coast
this afternoon. Local gusts up to 35 mph are possible in the
windier coastal locations from late afternoon through early
evening.

An upper level ridge is forecast to build over California during
the next few days, resulting in dry weather and a warming trend
through Wednesday. By Wednesday, high temperatures will be mostly
in the upper 60s and 70s, with a few lower 80s possible in
Monterey and San Benito counties.

Daytime temperatures on Thursday will cool by 5 to 10 degrees as
an inside slider type system drops inland to our east. The GFS
keeps all precipitation with this system to our north and east,
but the European model (ecmwf) tracks the system a bit farther to the west and
clips the northern and eastern fringes of our area with light
shower activity late Wednesday night and Thursday morning. Either
solution will result in blustery conditions in the hills and near
the coast by Thursday afternoon when locally strong northwest
winds develop. Northerly winds will ease near the coast by Friday,
but remain locally strong and gusty in the hills into Friday
night.

Upper level ridging is forecast to redevelop over California just
in time for the weekend, and current model projections indicate
dry and seasonably warm weather on both Saturday and Sunday.

&&

Aviation...as of 4:55 am PDT Monday for 12z tafs. Winds have
switched to the northwest overnight with a weak frontal passage.
Expect VFR conditions to prevail after 16z. There are a few low
clouds around ksfo and kmry as of 11z, but not expecting there to
be significant impacts as the boundary layer continues to dry
through the day. West to northwest winds can be expected this
afternoon with possible gusts exceeding 25 kts in the afternoon.

Vicinity of ksfo...MVFR conditions early this morning with a few
low cloud decks. Expect ceilings to improve by 16z as drier air
continues to move in. West to northwest winds will become gusty
this afternoon in excess of 20 to 25 kts.

Sfo bridge approach...similar to ksfo.

Monterey Bay terminals...a few low clouds continue to impact kmry
this morning with ceilings around 3000 ft. Expect VFR conditions
by mid-morning with gusty west to northwest winds this afternoon,
notably at ksns.

&&

Marine...as of 04:47 am PDT Monday...northwest winds will
increase this afternoon through at least Tuesday as a strong
surface pressure gradient builds across the region. At the same
time, a building northwest swell will pass through the waters.
Typical gusty Spring Time northwest winds will continue at least
through midweek and likely through Friday as the next weather
system will likely increase the surface pressure gradient once
again.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 0-10 nm from 12 PM
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm from 12 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm from 12 PM
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm from 12 PM
Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm from 12 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...mry Bay from 12 PM
Small Craft Advisory...sf Bay from 12 PM

&&

$$

Public forecast: Bell/dykema
aviation: Rowe
marine: Rowe



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