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.

Unsettled weather should continue across the forecast area as a low pressure slowly approaches. The forecast calls for clouds and scattered rain and snow showers that do not produce any accumulation today and tomorrow. As the day warms up, the chances for showers increase due warm air rising through the atmosphere. Daytime highs should increase some over the next two days and reach into the low to mid 40's today and mid to upper 40's tomorrow above 7000 ft. The moderate southwest winds should also continue today. By tomorrow these winds should decrease. 

Recent Observations:

Yesterday, observations on Carson Pass (photos, snowpit more info) and on Castle Peak (photos, snowpit more info) indicated snowpack consisting of melt-freeze crusts and well consolidated rounded snow on the northerly aspects. In both areas snowpit data, ski cuts, and other observations did not reveal any signs of snowpack instability on the these aspects. A frozen melt freeze crust also exited on the surface of the northerly aspects in both areas. The aspects on the southern half of the compass held melt-freeze conditions in various states. On Castle Peak above 8000 ft. the surface remained frozen and supportable throughout the morning due to cloud cover. Below 7600 ft. very little overnight refreeze had occurred and areas of punchy unsupportable snow existed in the Castle Peak area. In the Carson Pass area, fewer clouds and more sunshine allowed 2-3 inches of soft wet corn snow to form on the surface on the E-SE-S-SW aspects. This wet snow existed above a supportable melt-freeze layer. In both of these areas the sun-exposed southerly aspects have lost significant amounts of snow and large areas of exposed ground have melted out.

Avalanche Problem #1: Loose Wet Avalanches

A weaker overnight refreeze due to warmer temperatures and more widespread cloud cover combined with slightly warmer daytime temperatures should allow wet snow to form today. More consistent cloud cover that blocks the sunshine should help limit some of the melting that occurs today. Since the snowpack has undergone several melt-freeze cycles, well established drainage channels exist through the snowpack in many places. These drainage channels help move free water through the snowpack and prevent it from weakening the snowpack as much as it does when the water pools in one layer. Even though some wet snow may form on the surface today, significant wet snow instabilities remain unlikely. Some small wet snow instabilities like point releases and roller balls may form in very isolated areas if more sunshine or rain occurs today than the forecast calls for.

The bottom line:

Avalanche danger is LOW for all elevations and aspects. Continue to use normal caution when travelling in the backcountry.

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

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

0600 temperature:	29-33 deg. F.
Max. temperature in the last 24 hours:	35-46 deg. F.
Average wind direction during the last 24 hours:	Southwest
Average wind speed during the last 24 hours:	25 mph
Maximum wind gust in the last 24 hours:	52 mph
New snowfall in the last 24 hours:	O inches
Total snow depth:	48-84 inches

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

For 7000-8000 ft:
	Thursday:	Thursday Night:	Friday:
Weather:	Mostly cloudy with isolated showers throughout the day.	Mostly cloudy with isolated showers.	Mostly cloudy with a slight chance of showers.
Temperatures:	40-47 deg. F.	30-35 deg. F.	46-52 deg. F.
Wind direction:	Southwest	Southwest	Variable
Wind speed:	15-20 mph with gusts to 30 mph	10-15 mph with gusts to 25 mph decreasing after midnight	Light
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Thursday:	Thursday Night:	Friday:
Weather:	Mostly cloudy with isolated showers throughout the day.	Mostly cloudy with isolated showers.	Mostly cloudy with a slight chance of showers.
Temperatures:	34-41 deg. F.	25-30 deg. F.	40-48 deg. F.
Wind direction:	Southwest	Southwest	Southwest
Wind speed:	15-25 mph with gusts to 35 mph	20-25 mph with gusts to 35 mph decreasing to 10-15 mph after midnight	10-15 mph decreasing in the afternoon
Expected snowfall:	O in.	O in.	O in.