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fxus66 ksto 201110 
afdsto

Area forecast discussion
National Weather Service Sacramento California
410 am PDT Fri Oct 20 2017




Synopsis...
frontal system bringing rain and snow to the Sierra this morning.
A few inches of snow possible above 7000 feet. Showers possible
northern mountains through Saturday. Warming temperatures through
early next week. Slightly cooler temperatures for the second half
of the week but remaining dry and warmer than normal.

&&

Discussion...
back edge of frontal band dropping southeast through northern
California now along a line from about Blue Canyon to Modesto.
Precipitation amounts with this system have maxed out around 1
inch with around 1/2 inch common. The front will drop southeast of
the County Warning Area by 18z. Models bring another shortwave system through the
Pacific northwest this afternoon for a continued threat of
showers over the northern mountains through this evening.
Temperatures continue to cool today with daytime highs expected
to drop to about 10 to 15 degrees below normal. Upper ridging will
bring some warming on Saturday but another shortwave riding over
this ridge will bring another threat of light showers over the
northern mountains again through the day. The upper ridge
continues to build over the West Coast on Sunday for more warming
with any precipitation threat being pushed well north of the
forecast area. Highs on Sunday with push upward to near normal for
this time of year. Daytime highs are forecast to climb another 5
to 10 degrees on Monday as the upper ridge amplifies along the
West Coast.

&&
Extended discussion (tuesday through friday)

Warm and dry conditions will dominate norcal during the extended
forecast period as high pressure lingers over the region. Daytime
highs will range 10-15 degrees above normal through Thursday.
Valley highs will remain in the mid to high 80s while the
foothills and mountains will range in the 70s to 80s. Could see
gusty winds Monday in the western Sacramento Valley as the ridge
axis increases over the West Coast. Hec/jbb
&&

Aviation...

VFR conditions have returned and winds at taf sites are on the
decline as the cold front moves eastward into the Sierra. As of
10z, precipitation has moved east of most taf sites, however, ksck
still has -ra which will end in the next hour. Light north to west winds
at taf sites today at less than 10 kts. Jbb



&&

Sto watches/warnings/advisories...
Winter Weather Advisory until 11 am PDT this morning for West
Slope northern Sierra Nevada-western Plumas County/Lassen park.

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