This avalanche advisory is provided through a partnership between the Tahoe National Forest and the Sierra Avalanche Center. This advisory covers the Central Sierra Nevada Mountains between Yuba Pass on the north and Ebbetts Pass on the south. Click here for a map of the forecast area. This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires 24 hours after the posted time unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.

The high pressure ridge over the area should allow another day of unseasonably warm weather. As a cold low pressure system begins to replace this ridge, clouds should start to build over the region this afternoon. The winds should also shift to the southwest and increase today ahead of this system. By tonight the storm should arrive bringing even stronger winds and some snow. The forecast calls for the snow to continue through tomorrow with 3-7 inches of new snow expected below 8000 ft and 6-12 inches along the Sierra Crest. By tomorrow evening the snow and wind should start to decrease in intensity.

Recent Observations:

Observations around the forecast area continue to show a mostly frozen and stable snowpack. On Pyramid Peak (photos, snowpit, more info) and around Carson Pass (snowpit, more info) yesterday, the surface rain crust remained icy and supportable on most slopes. A small layer of weak sugary snow (facets) has formed between this surface crust and a much thicker, stronger frozen rain crust that exists deeper in the snowpack. The facets between these two crusts could become a problem as the surface crust deteriorates over time or once a large load falls on top of the snowpack. On the more sun exposed southerly aspects a shallow layer of soft corn snow did form around Carson Pass and on Pyramid Peak. Once the sun left the slopes, this layer of soft snow quickly started refreezing.

Avalanche Concerns:

Similar to yesterday only a small amount of short-lived melting and softening should occur today due to the weak December sunshine and relatively cool daytime highs. This melting should allow some shallow soft corn snow to form on the sun-exposed southerly aspects; however, it should not introduce enough water into the snowpack for wet snow instabilities to form. Even though avalanche activity remains unlikely today the icy snow surface will make falls much more difficult to control or arrest.

The bottom line:

The avalanche danger remains LOW for all elevations and aspects. Continue to use normal caution when traveling in the backcountry. Icy slopes pose the greatest hazard by making long sliding falls that are difficult to control or arrest a real possibility today.

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

Weather Observations from along the Sierra Crest between 8200 ft and 8800 ft:

0600 temperature:	33-35 deg. F.
Max. temperature in the last 24 hours:	37-45 deg. F.
Average wind direction during the last 24 hours:	Northeast
Average wind speed during the last 24 hours:	15-20 mph
Maximum wind gust in the last 24 hours:	39 mph
New snowfall in the last 24 hours:	O inches
Total snow depth:	34-46 inches

Two-Day Mountain Weather Forecast - Produced in partnership with the Reno NWS

For 7000-8000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny with some clouds developing over the area by this afternoon.	Mostly cloudy with a chance of snow after midnight.	Snow
Temperatures:	43-48 deg. F.	19-24 deg. F.	22-27 deg. F.
Wind direction:	Southwest	Southwest	Southwest
Wind speed:	15-20 mph with gusts to 30 mph increasing to 25-30 mph with gusts to 50 mph in the afternoon	30-40 mph with gusts to 55 mph	20-30 mph with gusts to 50 mph decreasing to 40 mph in the afternoon
Expected snowfall:	O in.	up to 2 in.	3-5 in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny with some clouds developing over the area by this afternoon.	Mostly cloudy with a chance of snow after midnight.	Snow
Temperatures:	40-45 deg. F.	14-21 deg. F.	16-23 deg. F.
Wind direction:	West shifting to the Southwest	Southwest	Southwest
Wind speed:	25-30 mph with gusts to 45 mph increasing to 40-45 mph with gusts to 70 mph in the afternoon	40-50 mph with gusts to 75 mph	35-45 mph with gusts up to 70 mph decreasing to 60 mph in the afternoon
Expected snowfall:	O in.	up to 3 in.	4-6 in. - Along the Sierra Crest up to 9 in.