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fxus66 kmtr 270405 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
905 PM PDT Mon Jun 26 2017

Synopsis...seasonably cool temperatures through midweek then
slight warming as a ridge builds Thursday and Friday. Slight
cooling back towards normal over the weekend as the ridge breaks
down. Dry weather the next 7 days with night and morning coastal
clouds followed by sunny afternoons.

&&

Discussion...as of 9:00 PM PDT Monday...a weak upper level
trough passed through northern California today. This deepened the
marine layer to 2500 feet and kept temperatures near normal
around the sfo Bay area today. Upper level ridge still has a hold
on Southern California and temperatures in the southern interior
were still in the 95 to 100 range. Stratus clouds are mixed out
but the presence of the marine layer should allow for increasing
coastal low clouds tonight.

Temperatures will remain near seasonal normals on Tuesday as
another weak disturbance passes north of the area. Warmer
temperatures are then expected inland Wednesday through Friday as
an upper level ridge builds off the California coast. Highs by
the end of the work week will warm back up to the upper 80s to low
90s but heat concerns are not expected. With the upper ridge off
the California coast the cool onshore flow will continue at the
coast with night and morning low clouds. Inland temperatures will
cool slightly during the weekend as the ridge breaks down.

Looking ahead to the 4th of July Holiday the pattern looks zonal
Sunday through Monday then a trough may dig into the Pacific
northwest but the end result for the Bay area would likely mean
some dry north winds that could keep marine clouds to a minimum.
Were heading towards the peak of the Summer doldrums here with no
precipitation in the forecast with the marine layer likely to set
up long term residence for July and August.

&&

Aviation...as of 4:47 PM PDT Monday...clouds have cleared out
very nicely this afternoon making way for clear skies across the
region. Low clouds are anticipated to return tonight under a deep
2000+ ft marine layer. Brisk onshore flow will prevail through
this evening then gradually diminish overnight.

Moderate confidence with regard to the timing of the cigs across
all terminals.

Vicinity of ksfo...VFR through this evening. MVFR cigs returning
between 03z-07z tonight. Cigs may be in and out at first, have
included a tempo group to reflect this. Cigs will fill in for the
night after 07z and persist till around 18z Tuesday morning.
Moderate and gusty winds around 15 to 20 kt with gusts to around
25 kt expected through late tonight. Winds will ease overnight
then strengthen once again to around 15 kt with gusts to 25 kt after
21z Tuesday.

Sfo bridge approach...similar to ksfo.

Monterey Bay terminals...VFR through this evening. MVFR cigs returning
between 03z-07z tonight. Cigs may be in and out at first, have
included a tempo group to reflect this. Cigs will fill in for the
night after 07z and persist till 17z-18z Tuesday morning.
West winds around 10 kt expected through late tonight. Winds will
ease overnight then strengthen once again to around 12-15 kt
after 19z-20z Tuesday.

&&

Marine...as of 1:28 PM PDT Monday...high pressure remains
located over the eastern Pacific. Locally gusty winds are forecast
along the immediate coast and in San Francisco Bay today. A
dominant southerly swell will persist into Wednesday morning.

&&

Mtr watches/warnings/advisories...
... Bay until 9 PM
Small Craft Advisory...mry Bay until 9 PM
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm until 9 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm

&&

$$

Public forecast: west pi
aviation: CW
marine: canepa



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