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 January 18, 2008 7:00 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:

Avalanche danger is LOW for all elevations and aspects. Normal caution is advised.

Temperatures should be slightly warmer today. The northeast flow should continue to bring moderate east and northeast winds through this evening. The winds should shift to the west and temperatures should warm more tomorrow as a small storm approaches the forecast area.
Cold temperatures and strong east winds are keeping the snow surface hard and frozen. This trend should continue today even though the forecast calls for slightly warmer temperatures. Some softening may occur on sun exposed aspects below 8000' today. However, the east winds, low sun angle, and short daylight hours should prevent the snow surface from softening very much in most areas. Observers continue to see surface hoar formation in sheltered areas below treeline near Donner Pass, north of Squaw in the Silver Peak area, and in the Mount Rose area. As this surface hoar continues to form during the cold, clear nights and as the winds diminish, the surface hoar should become more widespread. The strong east winds prevented this surface hoar from spreading into more exposed areas. If it does not get destroyed before the next storm, this layer will be one to watch out for. It is a great time to go check out your favorite backcountry stash to see what is happening on the surface and below the surface in the snowpack. The strong melt-freeze crust continues to hold most of the surface snow in place and to prevent the east winds from transporting much snow. Observations continue to show a well bonded snowpack throughout the forecast area.

The surface of this snowpack is a mix of wind scoured hard pack, frozen melt-freeze crusts, and some pockets of unconsolidated snow on the more sheltered northerly aspects. Wind protected N-NW aspects above 9000' have the most continuous and consistent areas of this unconsolidated snow. The riding in these areas remains nice.

The bottom line: Avalanche danger is LOW for all elevations and aspects. Normal caution is advised.
Please send us your snow, weather, and avalanche observations by clicking the submit observations link on our contact page.

Andy Anderson, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 20 deg. F
Max. temperature at Sierra Crest past 24 hours: 25 deg. F
Average wind direction at Sierra Crest past 24 hours: East
Average wind speed at Sierra Crest past 24 hours: 42 mph
Maximum wind gust at Sierra Crest past 24 hours: 70 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 55 inches
Mountain Weather Forecast For Today:
Sunny.
Temperature forecast for 8,000 to 9,000 feet: around 30 deg. F
Ridgetop winds forecast for the Sierra Crest: East at 20 to 30 mph with gusts to 65 mph in the morning decreasing in the afternoon.
Snowfall expected in the next 24 hours: 0 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, mostly sunny skies with daytime highs around 34 deg. F. East winds at 10 mph.

Tonight, clear skies with overnight lows 16 to 22 deg. F. East winds at 10 mph becoming light after midnight.

For Saturday, sunny skies with daytime highs around 39 deg. F. Light winds shifting to the west and northwest.

Above 8000 Feet:
Today, mostly sunny skies with daytime highs around 30 deg. F. East winds at 20 to 30 mph with gusts to 65 mph in the morning decreasing in the afternoon.

Tonight, clear skies with overnight lows around 22 deg. F. East winds at 15 to 20 mph with gusts to 40 mph.

For Saturday, sunny skies with daytime highs around 38 deg. F. West winds at 10 mph shifting to the northwest at 15 to 25 mph with gusts to 45 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.