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Area forecast discussion 
National Weather Service Sacramento California
336 PM PST Sat Jan 24 2015

dry weather with areas of night and morning valley low clouds and
fog through Monday. Temperatures expected to remain well above
normal through early next week in fog-free areas. Light
precipitation is possible Tuesday and Wednesday next week.


clear skies cover the region except for persistent low clouds in
the Central Valley. Offshore flow is working to clear the stratus,
and it looks like much of the remaining cloudy areas in the valley
will get to see at least a little sun before sunset. Temperatures
are very mild in the cloud free areas at the north end of the
valley and in the foothills and mountains. Redding and Red Bluff
are both currently in the mid 70s and will be making a run at 80
this afternoon. Meanwhile, Stockton and Modesto are both still
stuck in the stratus and are currently only in the mid 40s.

Strong upper high transits the area tonight and Sunday, and
offshore flow is forecast to continue. Fog and low clouds are once
again expected to develop and spread north through the valley
tonight, though models continue to indicate a shallower inversion
over the valley due to the offshore flow above the inversion, so
an earlier clearout will be possible on Sunday.

The upper ridge shifts east of California on Monday, with some
synoptic cooling expected that day. We should also begin to see
increasing high cloud cover later on in the day as a system off
the Baja California coast moves northward.

Computer models are in better agreement on the track and timing of
this system. Looks like some precipitation will be possible along
the Sierra beginning Monday night and spreading northward on
Tuesday. Snow levels are currently expected to be around 6000-7000
feet, but only minor snow accumulations are expected. The valley
has lower odds of seeing precipitation, but can't completely rule
out a sprinkle or light shower.


Extended discussion (wednesday through saturday)

The weak low which is expected to develop off Baja California and track
through the Sierra should been mainly out of the area by early
Wednesday. There may be just a lingering light shower over the
Sierra crest with dry weather for the rest of the area. On
Thursday and Friday, a weak trough develops to the south and
becomes an upper low, with some moisture spreading into the Sierra
south of i80. High clouds will be the main affect for most of the

The upper low is forecast to slowly shift southward Saturday
and may spread a few very light showers northward up the Sierra
as far north as Tahoe. The rest of the forecast area will see
variable high cloudiness going into next weekend with daytime
highs remaining well above normal for the northern Sacramento
Valley under upper ridging. Temperatures further south expected
to be near to a little above normal. Ek



Fog/stratus eroding from the north and still remains in the nrn
San Joaquin Valley as of 200 PM PST. Ksck/kmod will struggle to
break out prior to sunset. Low clouds/fog returning tonight, but
may stay mostly south of Sutter Buttes as light north wind may impede
spread northward and into wrn SAC valley. Elsewhere...VFR. Light
winds foggy areas...otherwise north to east winds 5 to 15 knots
with gusts to 25 knots over Sierra. Jclapp


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