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Area forecast discussion 
National Weather Service San Francisco Bay area
1045 PM PDT Tuesday Jun 2 2015

Synopsis...dry weather will persist through at least Thursday with
temperatures generally below seasonal averages. An upper level low
will bring the possibility of showers this weekend.

&&

Discussion...as of 9:47 PM PDT Tuesday...temperatures today were
fairly close to normal...within 2 to 3 degrees of normal for early
June. The theme was pretty much warmer temperatures inland valleys
as well as cooler temperatures at the immediate coast compared to
yesterday's readings.

A weak upper level trough over northernmost California continues to move
east and will reach northwest Nevada early Wednesday morning. In the interim
a deeper trough over the eastern Pacific will approach the Bay area
and central coast late tonight through Wednesday lowering 500 mb
heights. The trough will become a closed off middle level low circulation
late Wednesday night and continue to move south reaching the central
coast Thursday afternoon. There's only spotty very light quantitative precipitation forecast amounts
forecasted by the models through middle to late week...basically next to
dry area-wide. Increased amplification in the 500 mb height pattern
across the Gulf of Alaska to the Pacific northwest will produce an
unstable ridge and ageostrophic jet stream winds over the top of the
ridge will enter the back side of the closed upper low over California possibly
stalling the low's forward progression...at least temporarily. Forecast
confidence regarding the low's progression is low to moderate by late
week.

&&

Aviation...as of 10:45 PM PDT Tuesday...the northerly surface
gradient from sfo-acv has increased one mb to 4.9 mb this evening
clearing any lingering stratus from the coast. Low clouds are expected
to return late tonight. However the swath of high clouds currently
stretched across the region is making it hard to see exactly what
is going on beneath this layer. Latest observation show a few low clouds
over area terminals with exception to kmry that is ovc012. Stratus
will scatter out by noon Wednesday. Gusty onshore flow will
return again Wednesday afternoon. Moderate confidence.

Vicinity of ksfo...IFR ceilings are anticipated to return around 08z
and 10z over koak and ksfo respectively. Ceilings will scatter out
around 19z. Moderate onshore flow between 10 to 15 knots with gusts
to near 20 knots will continue through late tonight over ksfo. Winds
will ease to under 10 knots overnight. Gusty seabreeze will return
again Wednesday afternoon.

Ksfo bridge approach... similar to ksfo.

Monterey Bay area terminals...IFR ceilings have filled in over kmry
with ksns expected to go IFR around 10z tonight. Clearing is
expected around 18z-19z Wednesday. Light south to southwest winds
around 5 to 10 knots expected overnight. Gusty seabreeze will return
again Wednesday afternoon.

&&

Marine...as of 9:00 PM PDT Tuesday...high pressure building over
the eastern Pacific will generate moderately strong winds across
the coastal waters. Gusty winds will persist through Friday with
hazardous conditions and steep wind waves.

&&

Mtr watches/warnings/advisories...
... Pt to pt pinos 0-10 nm
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt Arena to pt Reyes 10-60 nm
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm
Small Craft Advisory...Pigeon pt to pt pinos 10-60 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm
Small Craft Advisory...Monterey Bay until 3 am

&&

$$

Public forecast: canepa
aviation/marine: CW

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