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419 AM PST Sun Dec 21 2014

Diminishing showers today, mainly in the mountains. Dry Monday and
Tuesday under high pressure ridge with patchy fog. There is a chance
another system may affect the region Wednesday into early Christmas


Upper level ridging over the eastern Pacific is gradually shifting
eastward with a warmer airmass over the region. Current temperatures
are 3 to 4 degrees warmer this morning compared to Saturday
morning. Overcast stratus is spread over the area and is limiting fog
development with just some misty patches for the morning. Could
see some light drizzle with the low clouds this morning in the
northern San Joaquin and southern Sacramento Valley. Abundant
precipitable water remains over the area (around 1.0 inch), though
dynamics are very limited. Warm advection will bring some light rain
showers for the northern Sacramento Valley today, with better
chances for the mountains. Additional rainfall amounts up to around
1 to 2 tenths of an inch possible over the Shasta County
mountains today, lesser amounts elsewhere. Just a a few lingering
showers possible over the northern mountains tonight. Snow levels
today are quite high with the relatively warm air mass over the
area, so no winter travel concerns today.

Ridging will bring dry weather and very mild temperatures for
Monday and Tuesday. Fog will begin to become an issue with
lingering low level moisture clearing skies and light winds. This
could limit temperatures in some Valley locations if it persists.

A weak system in northwest flow may brush through the area late
Wednesday into early Thursday. Moisture should be limited with this
system. It could be cool enough to bring some snow into the
mountains, but amounts look like they would be relatively light. EK

.Extended Discussion (Thursday through Sunday)

Drier northwesterly flow moves over the area in the wake of the
Christmas Eve system heading into next weekend. This will return
dry weather to the region and bring cooler overnight temperatures.



Widespread IFR/MVFR conditions continue across Valley TAF sites as
abundant moisture remains over the region. IFR/LIFR conditions 
will continue over the mountains. Snow levels rise above 090


.STO Watches/Warnings/Advisories...


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