PINK = Winter Storm Warning. PURPLE = Winter Weather Advisory. image: noaa, today

NOAA has issued a Winter Storm Warning for Lake Tahoe on Sunday.

8-24+ inches of snow are forecast.

* WHAT...Heavy snow expected. Total snow accumulations of 4 to 8 inches, 
except 8 to 16 inches above 7000 feet expected. Some locations along the 
Sierra Crest could see over 2 feet of snow. Winds gusting as high as 80 mph 
over ridges with gusts up to 40 mph elsewhere. - NOAA Reno, NV today

The Legendary Fingers of Squaw Valley on 1/18/19. image: snowbrains

NOAA has issued a Winter Weather Advisory for Mammoth on Sunday.

4-12″ inches of snow are forecast.

* WHAT...Snow expected. Total snow accumulations of up to 4 inches, 
except 4 to 12 inches above 7000 feet expected. Winds gusting as high 
as 75 mph over the ridges with gusts up to 50 mph elsewhere. 
- NOAA Reno, NV today

Mammoth Mountain, CA 1/16/19. Image: Peter Morning/ MMSA

Snow levels are forecast to start at 7,000′ on Sunday before crashing down as low as 3,000′ on Sunday night.

Snow levels will be around 7000 feet during the day on Sunday,
with snow mainly affecting the passes around Tahoe. 

Around 4 PM, snow levels crash down to Lake Tahoe level and down
to valley floors in western Nevada by 10PM Sunday night. Now this
is a precipitous drop in snow levels, an impressive 3000 feet
lower within 6 hours. 
-NOAA Reno, NV today

NOAA is talking about the potential of some very big snowfall totals on Sunday:

Our best estimates for snow totals will be around 4-8" around the
Lake Tahoe Basin (6000-7000ft), with up to 1 to 2+ feet above
7000 feet. If snow levels fall quicker than anticipated, those
numbers could be doubled. 

Snow amounts will be less in Mono County as the storm system
loses much of it`s punch as it moves south. - NOAA Reno, NV today

GEM Model showing big snow in California next few days. image: tropicaltidbits.com

Winter Storm Warning for Lake Tahoe:

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
1210 PM PST Sat Jan 19 2019

Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Truckee, Stateline,
and Incline Village
1210 PM PST Sat Jan 19 2019

...WINTER STORM WARNING IN EFFECT FROM 10 AM SUNDAY TO 4 AM PST
MONDAY...

* CHANGES...upgraded to Winter Storm Warning.

* WHAT...Heavy snow expected. Total snow accumulations of 4 to 8
  inches, except 8 to 16 inches above 7000 feet expected. Some
  locations along the Sierra Crest could see over 2 feet of snow.
  Winds gusting as high as 80 mph over ridges with gusts up to 40
  mph elsewhere.

* WHERE...Greater Lake Tahoe Area.

* WHEN...From 10 AM Sunday to 4 AM PST Monday.

* ADDITIONAL DETAILS...Travel could be very difficult at times.
  Snow levels will be around 7000 feet, affecting mountain passes
  during the daytime. Snow levels will then crash down to Lake
  Tahoe level after sunset. This will create widespread difficult
  travel conditions for Sunday evening. Strong winds could cause
  damage to snow laden trees.

Jared Dalen going big off My Air on 1/18/19. image: snowbrains

Winter Weather Advisory for Mammoth

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
1210 PM PST Sat Jan 19 2019

Mono County-
Including the cities of Bridgeport, Coleville, and Mammoth Lakes
1210 PM PST Sat Jan 19 2019

...WINTER WEATHER ADVISORY IN EFFECT FROM 4 PM SUNDAY TO 4 AM PST
MONDAY...

* CHANGES...upgraded to Winter Weather Advisory.

* WHAT...Snow expected. Total snow accumulations of up to 4
  inches, except 4 to 12 inches above 7000 feet expected. Winds
  gusting as high as 75 mph over the ridges with gusts up to 50
  mph elsewhere.

* WHERE...Mono County.

* WHEN...From 4 PM Sunday to 4 AM PST Monday.

* ADDITIONAL DETAILS...Travel could be very difficult at times.
  Strong winds could cause damage to snow laden trees.