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Area forecast discussion 
National Weather Service San Francisco Bay area
905 am PDT Friday Oct 9 2015

Synopsis...high pressure across our area will lead to dry
weather along with above normal temperatures today. Highs will
slightly cool over the weekend as the ridge starts to flatten.
Low pressure over northern Mexico will move west out over the
Pacific waters and may be a factor in our weather late Tuesday
through Thursday of next week.

&& of 9:00 am PDT Friday...sunny conditions under a
strong ridge of high pressure will help to push temperatures to
above normal levels for almost all locations today across our
region. Current surface flow is over 1 mb from the west so many
coastal spots will likely stay in the 60s to middle 70s due to the
impact of the cooler water temperatures. Inland areas away from sea
breezes will warm into the 80s to middle 90s. The ridge will flatten
over the weekend leading to some cooling.

Latest guidance has greatly backed off on subtropical moisture
moving in from the southeast for the first half of next week. In
fact...both the European model (ecmwf) and GFS now keep our entire area dry through
at least Wednesday with just a few minor showers indicated on
Thursday over interior Monterey County.

Current grids appear to be on track so no major updates planned.

Previous discussion...mild temperatures across the district this
morning as high clouds spread over the forecast area. Early
morning temperature trends are generally running warmer than
yesterday at this time with many readings still in the 60s. Expect
warmer high temperatures today as the upper level ridge axis moves
east over California and into the Great Basin.

Highs are expected to level off somewhat during the weekend as the
upper ridge flattens in response to a trough moving across the
Pacific northwest. By early next week a Rex block sets up along
the West Coast as the closed upper low now over northern Mexico
moves west to off the Baja California California coast...with a ridge of high
pressure building along the coast to the north. Earlier model
runs did bring more of a possibility for showers associated with
this cutoff low across our area by Tuesday or Wednesday. Latest
medium range model runs...though...take the track of the low
farther west which keeps our area least through
Wednesday. The European model (ecmwf) finally tracks the low back over Southern
California late Thursday into Friday...with the potential for
showers across southern and central California. Have made little
changes to existing pop grids for now as confidence remains low.

&& of 5:56 am PDT area of high pressure
is in place over central and northern California this morning with
an extremely compressed marine layer. High clouds are passing over
the area inhibiting radiational cooling and suppressing fog
development. Light onshore flow should help the marine layer to
develop today resulting in the potential for marine stratus
tonight into Saturday morning.

Vicinity of ksfo...VFR is expected to prevail today. The sea
breeze is anticipated to reach 15 knots this afternoon. Stratus will
be possible at or around 0600z tonight.

Confidence is high throughout the day becoming moderate tonight
with the return of stratus.

Ksfo bridge approach...similar to ksfo.

Monterey Bay area terminals...VFR is anticipated to prevail today
with reduced visible and ceilings possible between 1200 and 1500z this
morning. The sea breeze will reach 10 to 15 knots this
afternoon...strongest in the Salinas valley. Stratus will be
possible at or around 0500z tonight.

Confidence is high throughout the day becoming moderate tonight
with the return of stratus.

&& of 3:06 am PDT Friday...the surface pressure
gradient will strengthen today resulting in increasing winds over
the coastal waters today. The strongest winds will occur south of
Big Sur. Relatively gentle seas will persist into the
weekend...but will be choppy during the afternoon and early
evening hours in response to the afternoon sea breeze. A moderate
period west to southwesterly swell generated by hurricane oho will
enter the waters this evening...lasting into the weekend.


Mtr watches/warnings/advisories...
... Pinos to pt Piedras Blancas 0-10 nm from 2 PM



Public forecast: Bell/Sims
aviation: Larry
marine: Larry

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