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fxus66 kmtr 280433 cca 
afdmtr

Area forecast discussion...corrected aviation discussion
National Weather Service San Francisco Bay area
930 PM PDT Mon Mar 27 2017

Synopsis...breezy conditions will continue tonight as a ridge of
high pressure builds into our region. Slightly cooler conditions
are expected on Thursday as a weather system moves into eastern
California and Nevada. 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 8:55 PM PDT Monday...high pressure will
continue to build over the eastern Pacific while ridging across
northern California tonight. The northerly gradient from acv to
sfo has strengthened from 2.4 mb this afternoon to 6.2 mb this
past hour. This will maintain moderately strong and gusty
northwesterly winds across the forecast area. The typical
locations in the North Bay mountains have seen gusts near 40 mph
this afternoon and evening. The Monterey Airport has also been
reporting sustained wind speeds of over 20 mph with gusts to near
40 mph. Breezy conditions will continue this evening and then
ease a bit overnight.

Aside from breezy conditions the high will bring warmer and drier
weather to the region through midweek with temperatures rebounding
into the mid 60s along the coast, the upper 70s inland and a few
80s scattered across the warmest inland valley locations.

The high will keep the storm track north through Wednesday before
a quick moving system dives down across the region Thursday
bringing a slight chance of rain to our area along with cooler
airmass. Latest model solutions keep the bulk of the precipitation
to our east with the best chance of any precip expected Thursday
morning. Temperatures are forecast to plummet an average of 5 to
10 degrees across the forecast area as the cooler airmass slides
across the region. Breezy northwest winds will also accompany this
system with the coastal waters, coastal ranges and elevated
terrain across the north and East Bay hills seeing the strongest
winds.

Temperatures will rebound once again to seasonal levels on Friday
and Saturday as high pressure builds back in over the eastern
Pacific and a thermal trough develops along the coast.

Model solutions deviate at this point with the GFS hinting at
cooler temps and a chance of rain brushing up against the North
Bay Sunday while the Euro maintains a ridge of high pressure
across the region. Will continue to monitor as the solutions come
to a consensus.

&&

Aviation...as of 9:30 PM PDT Monday...moderate to high confidence
VFR tonight and Tuesday under a drier pattern and high pressure.
A moderately strong acv-sfo pressure gradient along with vertical
momentum Transfer of winds from the lower levels to the surface
will help keep areas of gusty west-northwest winds going tonight into Tuesday.
Lower to mid level warming is underway, this evening's 00z Oakland
sounding already showed a temperature inversion based near 7 thousand
feet (near 800 mb level). It should be a little less windy Tuesday.

Vicinity of ksfo...occasional gusty west-northwest winds this evening and
overnight. VFR.

Sfo bridge approach...similar to ksfo.

Monterey Bay terminals...gusty west-northwest winds becoming lighter to near
10 knots tonight. Moderate to high confidence VFR tonight into
Tuesday.

&&

Marine...as of 8:51 PM PDT Monday...moderate and gusty northwest
winds will persist through midweek as a strong surface pressure
gradient builds over the region. In addition, a building northwest
swell will move through the coastal waters through late week. Moderate
to gusty northwest winds will then likely continue through late
week.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 0-10 nm
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm
Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm
Small Craft Advisory...rough bar advisory for sf bar
Small Craft Advisory...mry Bay until 3 am

&&

$$

Public forecast: CW
aviation: canepa
marine: rgass



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