Area Forecast Discussion
Issued by NWS Sacramento, CA

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FXUS66 KSTO 260505

905 PM PST Thu Dec 25 2014

Mainly dry weather will continue for the next week, with modest
north winds and colder overnight low temperatures. Stronger north
winds may be possible for the middle of next week.


The word of the night brought to you by your NWS is COLD!
The next few nights will be very cold and some frost in the valley
will likely start to form...especially for Friday night and
Saturday morning across most rural areas.

Not expecting much in the way of fog through the weekend other
than maybe a few patches near water ways in the central part of
the valley this weekend and mainly near the Delta and Northern
San Joaquin Valley. Main thing moving forward will be the cold
temperatures. Coldest this year at night Saturday morning with
sub-freezing temperatures likely for most valley areas and single
digits possible for some of the colder mountains valleys.

A strong ridge will amplify off the west coast into Canada and
an inside slider moves through the region Monday night through
Tuesday night to bring mainly snow chances to the mountains and
low chances to the valley. The system does not look like it will
have much in the way of precipitation but it will be followed by
strong winds and a lot of cold air advecting into the region from
Canada. By the middle to later part of next week many valley
locations could be cooling off at night into the mid 20s to upper
20s to cause some agricultural concerns and warming center


.Extended Discussion (Monday through Thursday)

The extended forecast continues to look cool and breezy, with
little potential for precipitation except for light snow showers
up in the Sierra early this week.

A cold trough originates from Alaska/northwestern Canada and drops
down into northern California on Tuesday. This system deepens and
spreads westward over the area, bringing cold air into the region.
700 mb temperatures drop to an impressive -15 C Monday
night/Tuesday morning as the core moves over the area. This should
bring teens and even some single digits to the higher mountains
for Tuesday morning. Temperatures there may not warm up much
during the day. This cold air will also squeeze out some snow
showers in that area, though moisture is lacking with this system.
Valley lows in the mid to upper 30s and highs in the 40s will seem
quite cool compared to the warm temperatures we have been seeing
in recent weeks.

Some breezy north winds are expected on Monday. Stronger winds are
expected on Tuesday, and may reach wind advisory levels
with sustained winds of 25 mph with stronger gusts. The winds should
keep the atmosphere mixed in the Valley and limit frost and colder
temperatures there.

By Wednesday/Thursday, the trough closes off and drops to the
south and east. Winds weaken allowing colder temperatures in the Valley.
The best chance for frost and freezing valley temperatures will
likely be Wednesday/Thursday when winds subside, especially on the
less windy eastern side of the valley. Highs in the mountains will
remain cold through the later half of the week. EK



VFR conditions through Friday. Local breezy northeast surface
wind gusts in the mountains to 30kt. Breezy/gusty north winds
return again for Friday for the valley with clear skies.


.STO Watches/Warnings/Advisories...

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