Scientific Forecaster Discussion
fxus66 kmtr 252052
Area forecast discussion
National Weather Service San Francisco Bay area
152 PM PDT sun Jun 25 2017
Synopsis...look for continued cooling inland through Monday as
the ridge of high pressure that had been overhead continues to
progress to the east. Also areas of night and morning low clouds
and fog followed by sunny afternoons can be expected. Modest
warming is expected during the second half of the week, however
highs will fall well short of the recent heatwave.
Discussion...as of 2:00 PM PDT Sunday...as expected temperatures
are running cooler than yesterday especially for inland
locations. Overall looking at a drop of 4 to 9 degrees away from
the coast with temperatures close to saturday's values.
Synoptically the strong high pressure ridge aloft has continued to
progress to the east while a more pronounced onshore flow is
setting up. Look for a quick return of the clouds this evening
along with patchy drizzle.
The ridge will continue to move to the east on Monday while 850 mb
temperatures drop another 2c down to the 19-21c range. Highs end
up being another 2 to 5 degrees cooler in most locations -- 70s to
mid 80s inland with mostly 60s at the coast. The only real
exception will be far southern Monterey and san bentio counties
where highs will still reach the 90s. Conditions on Tuesday will
A ridge of high pressure will attempt to rebuild into our region
starting Wednesday which will help to increase temperatures a bit,
however values will stay well below the very high numbers we had
recently. Generally look for 60s to lower 70s at the coast with
mid 70s to near 90 inland.
Longer range guidance through July 9th favors dry conditions with
temperatures near to a bit above normal.
Aviation...as of 10:53 am PDT Sunday...for 18z tafs...marine
layer depth remains at about 1800 feet with slow burn-off across
western tafs. Clearing expected most areas by early afternoon with
a strong seabreeze. Cigs return again tonight.
Vicinity of ksfo...MVFR cigs through roughly 19z. Satellite
indicates low clouds continuing to feed into The Gap with strong
onshore flow. Expect brief clearing at the terminal by 19z but
early return (04z) of MVFR cigs changing to IFR by 08z.
Sfo bridge approach...similar timing, although low clouds could
circulate around the Bay given the strong onshore push.
Monterey Bay terminals...LIFR cigs for kmry until 19z, then
changing to IFR. Clearing possibly by 20z with an early return.
Light west winds.
Marine...as of 8:32 am PDT Sunday...high pressure off the West
Coast will maintain northerly winds over the coastal waters
through next week. Winds will be locally stronger along the
immediate coast. Seas will be small with a dominant southerly
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Public forecast: Bell
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