NOAA has issued two Winter Storm Watches for California that are in effect Wednesday and Thursday this week.  This watch extends from Mt. Lassen down to the northern boarder of Yosemite National Park.

Heavy snow possible. Windy conditions possible. Plan on difficult travel conditions, 
including during the evening commute on Wednesday. Damage to trees and power lines is 
possible. Total snow accumulations of 8 to 12 inches, with localized amounts up to 18 
inches, are possible. Wind gusts 35 to 40 mph with gusts 50 to 70 mph on the highest 
peaks. - NOAA Reno, NV today

8-18″ of snow is forecast west of the Sierra Crest.

Total snow accumulations of 8 to 12 inches, with localized amounts up to 18 inches, 
are possible. - NOAA Reno, NV today

6-12″ of snow is forecast east of the Sierra Crest.

Total snow accumulations of a foot or more above 7000 feet. Accumulations below 
7000 feet are more uncertain and depend on how fast snow levels fall Thursday, 
but could reach 6 or more inches. - NOAA Reno, NV today

Snow levels are forecast to be around 6,000-7,000′ with heaviest accumulations above 7,000′.

NOAA is anticipating nasty travel delays over Sierra passes resulting from this storm.

Significant reductions in visibility are possible. VERY LONG TRAVEL DELAYS over 
Sierra passes possible Wednesday night through Thursday night. - NOAA Reno, NV today

Ski Resorts Open in California/Nevada Right Now:

• Boreal
• Mt. Rose
• Mammoth

Squaw Valley is scheduled to open on Friday.

Winter Storm Watch for West of Sierra Crest:

URGENT - WINTER WEATHER MESSAGE
National Weather Service Sacramento CA
144 PM PST Sun Nov 12 2017

...MOUNTAIN SNOW POSSIBLE WEDNESDAY INTO THURSDAY NIGHT...

.A storm system will move into the area on Wednesday and continue
through Thursday night. Latest model forecasts are not in
agreement in timing and snow levels. However confidence is
increasing that a winter storm will occur with accumulations up 8
to 12 inches, with localized amounts to 18 inches. Combination of
wind and snow will bring difficult mountain travel.

Western Plumas County/Lassen Park-
West Slope Northern Sierra Nevada-
144 PM PST Sun Nov 12 2017

...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY MORNING THROUGH
LATE THURSDAY NIGHT ABOVE 6000 FEET...

* WHAT...Heavy snow possible. Windy conditions possible. Plan on
  difficult travel conditions, including during the evening
  commute on Wednesday. Damage to trees and power lines is
  possible. Total snow accumulations of 8 to 12 inches, with
  localized amounts up to 18 inches, are possible. Wind gusts 35
  to 40 mph with gusts 50 to 70 mph on the highest peaks.

* WHERE...Western Plumas County/Lassen Park and the West Slope
  Northern Sierra Nevada.

* WHEN...From Wednesday morning through late Thursday night.

* SNOW LEVELS...Heaviest accumulations above 6000 feet.

* ADDITIONAL DETAILS...Significant reductions in visibility are
  possible under periods of heavy snow and windy conditions.

Winter Storm Watch for East of Sierra Crest:

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
330 PM PST Sun Nov 12 2017

Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Truckee, Stateline,
and Incline Village
330 PM PST Sun Nov 12 2017

...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH
LATE THURSDAY NIGHT...

* WHAT...Heavy snow possible...plan on difficult travel
  conditions. Possible damage to trees and power lines. Total snow
  accumulations of a foot or more above 7000 feet. Accumulations
  below 7000 feet are more uncertain and depend on how fast snow
  levels fall Thursday, but could reach 6 or more inches.

* WHERE...Greater Lake Tahoe Area.

* WHEN...From Wednesday afternoon through late Thursday night.

* ADDITIONAL DETAILS...Significant reductions in visibility are
  possible. VERY LONG TRAVEL DELAYS over Sierra passes possible
  Wednesday night through Thursday night.