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.

Northeastery winds and clear skies should persist through tonight due to a high pressure ridge over the forecast area. A small low pressure system moving south out of Canada should impact the forecast area starting Wednesday. This system should bring an increase in clouds, slightly warmer daytime highs, and moderate to strong westerly winds.

Yesterday, the east and northeast winds moved enough snow onto the exposed, high-elevation, SE-S-SW-W-NW aspects to form wind slabs on these slopes. Skiers caused shooting cracks by stepping on these wind slabs near the summit ridgelines on Becker Peak (near Echo Summit) and Hidden Peak (West Shore of Lake Tahoe). On SW side of the ridge on Hidden Peak a "whumph" occurred as the bonds between the newly formed wind slab and the snow below it collapsed due to a skier's weight. The Bear Valley Ski Patrol reported triggering several small avalanches during control work with ski cuts and explosives due to failure of these new wind slabs. The winds stripped all of the new snow off of several exposed, high-elevation N-NE facing slopes on Castle Peak (near Donner Summit) by mid-afternoon leaving the pre-storm crust on the surface. Across the forecast area the winds remained light to moderate below the ridgelines and left soft snow in place on slopes protected by trees or terrain features. This snow stayed cold and light on the shaded northerly aspects. On the E-SE-S-SW aspects the intense March sun started to melt the surface snow making it wet and heavy by midday. Expect to see a sun crust up to at least 8500' on these sun exposed aspects today.

The newly formed wind slabs sitting on the NW-W-SW-S-SE aspects near and above treeline will remain the primary avalanche concern today. Northeast and east winds continued to move snow last night and should have caused these wind slabs to grow larger and to become more widespread. The intense March sun will also weaken these new wind slabs making them more sensitive to human triggers. The cool daytime highs, persistent northerly winds, and gradual warming since the end of the storm should limit warming instabilities on the sun exposed aspects that do not have wind slabs on them. 

The bottom line:

Near and above treeline, MODERATE avalanche danger exists on SE-S-SW-W-NW aspects 35 degrees and steeper. Below treeline, avalanche danger is LOW.

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

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

0600 temperature:	17 deg. F.
Max. temperature in the last 24 hours:	29 deg. F.
Average wind direction during the last 24 hours:	Northeast
Average wind speed during the last 24 hours:	25 mph
Maximum wind gust in the last 24 hours:	64 mph
New snowfall in the last 24 hours:	O inches
Total snow depth:	150 inches

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

For 7000-8000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny	Clear in the evening then becoming partly cloudy	Partly cloudy in the morning becoming mostly cloudy in the afternoon
Temperatures:	30-40 deg. F.	22-32 deg. F.	35-45 deg. F.
Wind direction:	Northeast	North	West
Wind speed:	10 mph	10-15 mph	10-15 mph
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny	Clear in the evening then becoming partly cloudy	Partly cloudy in the morning becoming mostly cloudy in the afternoon
Temperatures:	25-35 deg. F.	20-30 deg. F.	30-40 deg. F.
Wind direction:	Northeast	Northeast	East shifting to the west
Wind speed:	10-15 mph with gusts to 30 mph	10-15 mph with gusts to 30 mph	15-20 mph with gusts to 30 mph increasing to 20-30 mph with gusts to 50 mph in the afternoon
Expected snowfall:	O in.	O in.	O in.