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Area forecast discussion 
National Weather Service Sacramento California
144 PM PST Friday Nov 27 2015

mainly dry conditions into this weekend with cold morning
temperatures. The next chance for precipitation will arrive
next week.


Short term discussion (today through monday)...
dry nly wind has lowered dewpoints into the teens to mid 20s over
most of interior norcal and this will likely preclude fog in the
valley once again. These lower dewpoints (dry air) will make it
problematic for frost...with moisture along the river valleys
perhaps enough of a catalyst in the wind-sheltered or lower lying
areas to provide enough moisture for what would be some light frost.

Weaker short energy will be rotating around the Great Basin low
and into norcal on Sat keeping local katabatic breezes over the
County Warning Area. Main short wave energy offshore will be rotating underneath
the Rex block over the Great Basin this weekend and finally ejecting
The Block ewd where it will weaken its influence over norcal on sun.
Much lighter winds and clear skies are expected over the region on
sun making it conducive for precipitous drops in temps below
freezing Sun morning...then warming into the 50s in the valley
during the afternoon. Jhm

Next system of interest may approach the West Coast during the day
Monday. Models currently depict wave fizzling out as it moves
onshore so limited chances for much precipitation with it with best
chances across northern and western portions of the area.



Extended discussion (tuesday through friday)
confidence is still not high in the extended forecast as the GFS
and European model (ecmwf) remain varied in their output. As things stand now, both
the GFS and ec agree that weak ridging will develop Monday night
into Tuesday for drier conditions across norcal. Overnight Tuesday
into Wednesday is when showers could impact our region again,
though the GFS limits these showers to Shasta County while the ec
spreads them as far south as Interstate 80. A deeper trough will
move into our region on Thursday but there are timing differences
on its arrival between the models and then showers should taper
off on Friday. Jbb



Sky clear at taf sites with nly winds gusting up to ~25 kts around the
krdd-krbl vicinity into Sat morning. Also...breezy NE to Ely winds
along western Sierra slopes.


Sto watches/warnings/advisories...
freeze watch from late Saturday night through Sunday morning for
Carquinez Strait and Delta-central Sacramento Valley-northern
Sacramento Valley-northern San Joaquin Valley-southern
Sacramento Valley.



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