Area Forecast Discussion
Issued by NWS Sacramento, CA

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FXUS66 KSTO 212314

314 PM PST Fri Nov 21 2014

The last in a series of weather systems will move into the area
later today into Saturday, bringing widespread precipitation. A
ridge of high pressure will build back in for the end of the
weekend into much of next week. This will allow for dry weather
and above normal temperatures. Areas of morning valley fog are
possible into the middle of next week with lingering moisture and
light winds.

Last in a series of systems is currently moving onshore across
NorCal this afternoon. Light precip will continue to overspread
the area from NW to SE during the evening hours becoming heavier into
Saturday morning. Latest hi-res guidance in agreement that, for
much of the area, bulk of precip will fall between 6Z-18Z Saturday
with this evening`s commute remaining dry. Forecast generally on
track with minor tweaks made to timing of highest POPs and QPF.
PWAT is fairly high for this time of year with values ranging from
0.75 to 1.5 inches. Forecast QPF values haven`t changed much from
this morning`s forecast with amounts ranging from 0.10-0.4" in the
valley to 0.5-1.5" in the foothills and mountains. Because of warm
nature of system, snow amounts will be limited as snow levels rise
above 7-8K feet by the time the majority of the precip arrives.
Light accumulations expected only at highest elevations with
minimal travel impacts expected. Other factor with this system
will be breezy conditions on Saturday. Sustained valley winds may
be on the order of 15-20 mph with gusts as high as 35 mph in some
locations. Mountain ranges will see gusts upward of 40-45 mph with
higher gusts near the Sierra crest.

Ridging builds back in over the coast for Sunday into the
beginning of next week. Dry weather is expected with above normal
temperatures. Valley fog certainly possible early Monday morning
with light winds and lingering moisture. CEO

.Extended Discussion (Tuesday through Friday)

Strong ridging will bring dry weather and light winds early next
week through Thanksgiving day. Travel conditions are expected to
be good through that period, except for locally dense fog in the
Valley at times. The light winds and mostly clear skies at night,
along with leftover moisture from recent storms could create good
conditions for fog development, but the exact location and timing details
will have to wait. Temperatures should be quite mild with a warm
airmass, though if fog manages to persist into the afternoon,
those areas could end up being cooler than forecast.

On Friday, models are suggestion a shortwave could bring some
precipitation into the coastal range and northern mountains. The
12z GFS and ECMWF also show this spreading into the northern
Sacramento Valley and the Sierra. have introduced a slight chance
of rain into those areas. Snow levels look to be above pass levels
at this point. EK



Light precipitation is gradually spreading from north to south into
interior Norcal. Most of the rain/snow occurring 06z. This will
bring widespread MVFR with local IFR cigs/vsbys across NorCal into
Saturday. Light winds for this evening, but southerly winds will
increase after 06z.


.STO Watches/Warnings/Advisories...

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