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fxus66 kmtr 262051 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
1251 PM PST sun Feb 26 2017

Synopsis...showers will be possible across the region from late
tonight through Monday as a frontal system moves across the
region. Rainfall accumulation will generally be light with snow
showers in the higher elevations. Dry weather conditions then
return for the remainder of the workweek along with a gradual
warming trend as high pressure builds aloft.

&&

Discussion...as of 12:50 PM PST Sunday...aside from cumulus
developing over the mountains/hills this afternoon, mostly sunny
conditions prevail ahead of an approaching weather system to our
north. The latest forecast models and current trends bring a
frontal boundary across the region late this evening and through
the overnight hours with isolated to scattered showers likely.
These showers will likely impact the North Bay late this evening
or tonight and shift southward through the central coast overnight
into Monday morning. Rainfall amounts in the range of a few
hundredths of an inch to a couple tenths will be possible yet not
all locations will pick up measurable precipitation. In addition,
snow levels are forecast to lower again to the 3,000-3,500 foot
range along the central coast with below 3,000 northward. Thus,
should see some snow showers across the region with light
accumulation in the higher elevations. Meanwhile, overnight
temperatures will remain in the 30s to lower 40s as this system
will bring a reinforcing shot of cooler air across the region.

Lingering showers will be possible into Monday morning before
diminishing in coverage by the afternoon and evening. Dry weather
conditions are then likely for the remainder of the week as high
pressure builds out over the eastern Pacific. Temperatures will
also begin a gradual warming trend late in the week with
widespread 60s likely by Thursday and Friday. Overnight
temperatures will also moderate some and only cool into the upper
30s to lower 40s by late week, compared to the lower/mid 30s more
common the next few nights.

The upper level ridge is forecast to weaken a bit by the upcoming
weekend as a mid/upper level through approaches the Pacific
northwest. At this time, the best chance of precipitation will be
north of the region yet cannot rule out the system clipping the
far northern portion of the North Bay by Saturday night into
Sunday. However, not expecting widespread heavy rainfall with most
locations remaining dry across the region through the extended
forecast period.

&&

Aviation...as of 03:34 am PST Sunday...generally VFR through the
forecast period although any passing showers could quickly lower
conditions rapidly. Models generally increase shower activity
after 05z so trended toward that in the tafs with vcsh. Moderate
confidence.

Vicinity of ksfo...mostly VFR expect during showers. Vcsh expected
starting around 06z. Generally light winds this morning
increasing to 10-15 kt west to northwesterly flow by this
afternoon. Moderate confidence.

Sfo bridge approach...similar to sfo.

Monterey Bay terminals...VFR. Light winds. Possible shower or two
after 05z so added vcsh. Moderate to high confidence.

&&

Beaches...a beach hazard statement was issued for the threat of
sneaker waves on Sunday. A long period swell arriving Sunday
morning, along with fair weather and light morning winds, will
bring a moderate risk of sneaker waves to North Bay and Bay area
coastal beaches. Arrival of the long period swell will coincide
with a rapidly rising tide on Sunday morning, pushing more energy
up the beach. West and northwest facing and steep sloped beaches
will be at greatest risk. The threat is expected to abate in the
afternoon as the tide drops, onshore winds develop, and long
period waves transition to shorter periods. Bfg

&&

Marine...as of 09:23 am PST Sunday...a weak system will enter the
area tonight bringing moderate to fresh northerly conditions
along with a few showers. Monday Onward conditions should remain
moderate to fresh with possible near gale conditions later this
week. No significant swell trains are expected through the
period.

&&

Mtr watches/warnings/advisories...
...

$$

Public forecast: rgass
aviation: Bell
marine: Bell



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