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000 
FXUS66 KSTO 172254
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
254 PM PST Sun Nov 17 2019

.SYNOPSIS... 
Dry and mild conditions this week. Very warm again on Monday with
record highs possible in the northern Sacramento Valley. Pattern 
change still on track around mid week with breezy to windy
conditions, cooler temperatures and possible rain/snow mainly in 
the Sierra Nevada.

&&

.DISCUSSION...
High pressure will remain over the region early this week. Light 
winds again tonight with less high clouds should allow for the 
redevelopment of fog for places south of Marysville and into the 
Delta. Mainly through the central parts of the valley and near 
waterways. Some record and near record temperatures the next 
couple of days.

On Tuesday a low pressure area will drop down from the north and
over the state. This will bring cooler temperatures and breezy 
north winds during the day for the valley. Offshore pressure 
pattern increases Tuesday night into Wednesday when the stronger
winds are expected to develop. A wind advisory may be needed for
the Sacramento valley, Delta, coastal range and northeast 
foothills/mountains on Wednesday. Some shower chances for Sierra 
Nevada Tuesday night and Wednesday as the low moves through the 
area but most areas look to remain dry.

&&
.EXTENDED DISCUSSION (Thursday THROUGH Sunday)...

Upper level low pressure over Southern California gradually exits
to the south and east on Thursday. The pressure gradient between 
this low and high pressure to the north will begin to relax 
through the day, with breezy winds gradually decreasing. A Fire 
Weather Watch continues from Tuesday night into early Thursday, 
with poor humidity recovery, extremely dry fuels and morning 
winds. These northeast to east winds could gust to 20 to 30 mph, 
locally higher over ridges and through northeast oriented canyons.

Some lingering light snow is possible over the higher elevations
of the northern Sierra early Thursday, south of Highway 50, 
before the system moves out. Storm totals of several inches of 
snow are possible at Ebbetts and Sonora passes. 

Daytime highs will be cooler than seen in recent days, but will
remain slightly above average through the period, with Valley 
highs in the mid 60s to low 70s. EK

&&

.AVIATION...


VFR conditions next 24 hours except local MVFR/IFR conditions 
from KSMF southward 12z-18z Mon. Winds generally below 10 kts.


&&

.STO WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from late Tuesday night through Thursday 
morning for Central Sacramento Valley in Glenn, Colusa, Yuba, 
Northern Sutter, and Butte County Below 1000 Ft-Eastern 
Mendocino NF-Eastern Portion of Shasta/Trinity NF-Lake County 
Portion of Lake-Napa-Sonoma Unit-Northern Sacramento Valley to 
Southern Tehama County Line Below 1000 Ft-Northern Sierra 
Foothills from 1000 to 3000 Ft. Includes portions of Shasta-
Trinity and Butte Units-Northern Sierra Including Lassen NP and 
Plumas and Lassen NF/S West of the Sierra Crest (West of Evans 
Peak-Grizzly Peak-Beckworth Peak)-Southeast Edge Shasta-Trinity 
NF and Western Portions of Tehama-Glenn Unit-Southern Sacramento 
Valley in Yolo-Sacramento Far Western Placer, southern Sutter 

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