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.

This advisory was posted on Friday, February 2, 2007 at 5:40 pm

The bottom line: Avalanche danger is LOW for all elevations and aspects. Human triggered avalanches are unlikely, but not impossible in very isolated areas near treeline on NW-N-NE aspects, 35 degrees and steeper.

Our next fund raiser is another ski day this Sunday, February 4th at Homewood. Tickets are on sale now at Snowbomb.com. If you can't make it but would still like to help out, please make a tax deductible donation directly to us via Paypal or by sending a check to our address listed above, c/o the Truckee Ranger Station. Your support is what makes the Sierra Avalanche Center possible. For more details on the current financial situation please click here.

A weather system is currently passing to the north of the forecast area. This is increasing cloud cover over the forecast area and is expected to gradually increase air temperatures throughout the forecast area over the weekend. Ridgetop winds are expected to remain light northerly through the weekend.

Snowpack temperatures on northerly aspects have remained cold throughout the forecast area. The faceting process continues to work on the snowpack, especially on northerly aspects at all elevations. Significant faceting has been observed at all elevations in the Mount Rose area. Along the Sierra Crest, significant faceting exists in the shallow snowpack below 8,000'. Above 8,000', a deeper snowpack ranging from 4-5 feet deep, is showing less faceting and overall better stability. Highly variable snowpack strength has been observed over the past few days. Layers of faceted snow and layer interfaces with crusts continue to yield moderate shear failure in response to layer bonding tests in the Mount Rose area and in some areas along the Sierra Crest in the 7,500' to 8,500' elevation range. Many areas above 8,500' along the Sierra Crest are showing a very stable snowpack due to greater depth and less faceting. Very isolated areas exist on northerly aspects where human triggered avalanches are unlikely but not impossible on faceted weak layers.

Faceting of surface snow below treeline on northerly aspects has created enjoyable, unconsolidated snow surface conditions in areas that have not been tracked by others. A daily melt-freeze cycle continues on southerly aspects.

No avalanche activity was reported today.

The bottom line: Avalanche danger is LOW for all elevations and aspects. Human triggered avalanches are unlikely, but not impossible near treeline on NW-N-NE aspects, 35 degrees and steeper.

The next scheduled update to this advisory will occur tomorrow afternoon.

Brandon Schwartz, Avalanche Forecaster

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Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 26 deg. F
Max. temperature at Sierra Crest past 24 hours: 46 deg. F
Average wind direction at Sierra Crest past 24 hours: easterly
Average wind speed at Sierra Crest past 24 hours: 22 mph
Maximum wind gust at Sierra Crest past 24 hours: 43 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 34 inches

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Mountain Weather Forecast For Saturday:
Partly cloudy skies.
Temperature forecast for 8,000 to 9,000 feet: 40 - 46 deg. F
Ridgetop winds forecast for the Sierra Crest: north 10 - 15 mph
Snowfall expected in the next 24 hours: 0 inches

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2 Day Mountain Weather Forecast:
7000 to 8000 Feet
Tonight, becoming clear with lows 16 to 26 degrees F. Northeast winds 10 to 15 mph. Saturday, partly cloudy skies with daytime highs around 47 degrees F. Winds are forecasted to be out of the north at 10 to 15 mph.

Above 8000 Feet
Tonight, becoming clear with lows around 22 degrees F. North winds 10 to 15 mph. Saturday, partly cloudy skies with daytime highs around 43 degrees F. Winds are forecasted to be out of the north at 10 to 15 mph.

The bottom line:

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

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

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

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

For 7000-8000 ft:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.