473 
FXUS66 KSTO 102200
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
300 PM PDT Wed Oct 10 2018

.SYNOPSIS... 
Weak weather systems will bring light showers to the Sierra today
and Thursday. Locally breezy north to east wind today into 
Friday. Temperatures remain near normal through Friday, then 
slightly above normal this weekend.

&&

.DISCUSSION...
Interior NorCal sandwiched between high amplitude ridging in EPAC
and deep longwave troughing over U.S. Water Vapor imagery showing
short wave trough dropping through NorCal under northerly flow 
aloft. Visible revealing clouds associated with this wave over 
the Sierra Nevada and 88-D indicating scattered light showers. 
Latest HRRR suggest showers will continue over higher elevations 
of the Sierra Nevada til around 07z. Light snow is possible over 
Sonora, Ebbetts, and Carson passes. Locally breezy northerly wind 
possible in Shasta county and Northern Sacramento Valley into
early evening.

Additional short wave trough drops south and digs offshore 
Thursday as upper ridging builds into the PacNW. Models keep a 
threat of showers over the Sierra Nevada with light snow again 
possible over the passes, above 8000 feet. NEly flow aloft 
develops over NorCal with locally gusty north to east wind. 
Strongest wind, gusts to around 30 mph, expected northern and 
western portions of the Sacramento Valley, east slopes of Coastal 
Range, eastern foothills and favorably oriented canyons of Western
Plumas mountains and Sierra Nevada. Drying downslope flow will 
lower humidities.

Offshore trough develops into upper low Friday and digs Saturday as
upper ridging continues to build over NorCal. Locally breezy wind
persists into Friday morning then gradient weakens some. Near 
normal temperatures today into Friday, then about 3 to 5 degrees 
above normal forecast this weekend.

PCH

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)
High amplitude upper ridging in EPAC extends inland along the 
West Coast Sunday into middle of next week with dry conditions. 
Highs will be slightly above normal with 80s in the Central 
Valley, and generally 60s to 70s for the mountains and foothills. 
Locally gusty north to east wind possible at times with lowering 
humidity.

&&

.AVIATION...
VFR conds ovr Intr NorCal nxt 24 hrs. Isold MVFR poss ovr Siernev
in -shra with -shsn poss abv 080 MSL til 07z. Lcl Nly sfc wnd 
gsts to 20 kts in ptns of nrn and wrn Sac Vly til 02z and agn aft 
16z Thu.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$