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 Avalanche Advisory was published on January 17, 2008:

January 17, 2008 at 1:00 am

Forecast Discussion:

This advisory was posted on January 17, 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.

The forecast calls for northeast flow and cold, sunny weather through Friday. Overall the east and northeast winds associated with this weather pattern should decrease some today. The maximum gusts should remain strong. This pattern should start to change Friday night and Saturday.
Cold temperatures and strong east winds allowed Wednesday night's hard refreeze to remain frozen all day yesterday. Similar conditions today should prevent the snow surface from softening very much. Observers reported some surface hoar formation in sheltered areas below treeline near Donner Pass yesterday. The strong east winds near and above treeline prevented this surface hoar from spreading into more areas. The strong melt-freeze crust locked most of the surface snow in place and prevented the east winds from transporting much snow away from the N-NE-E aspects yesterday. However, the winds did start to scour some of the cornices along these ridgelines. 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): 18 deg. F
Max. temperature at Sierra Crest past 24 hours: 20 deg. F
Average wind direction at Sierra Crest past 24 hours: East
Average wind speed at Sierra Crest past 24 hours: 50 mph
Maximum wind gust at Sierra Crest past 24 hours: 78 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: 28 to 32 deg. F
Ridgetop winds forecast for the Sierra Crest: East at 20 to 30 mph with gusts to 50 mph.
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 to 15 mph.

Tonight, clear skies with overnight lows 15 to 21 deg. F. East winds at 10 to 15 mph.

For Friday, sunny skies with daytime highs around 38 deg. F. Northeast winds at 10 to 15 mph with gusts to 25 mph.

Above 8000 Feet:
Today, mostly sunny skies with daytime highs around 32 deg. F. Northeast winds at 20 to 30 mph with gusts to 50 mph.

Tonight, clear skies with overnight lows 18 to 22 deg. F. Northeast winds at 20 to 35 mph with gusts to 50 mph.

For Friday, sunny skies with daytime highs around 37 deg. F. Northeast winds at 15 to 25 mph with gusts to 50 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:
  Thursday: Thursday Night: Friday:
Weather:
Temperatures: deg. F. deg. F. deg. F.
Wind direction:
Wind speed:
Expected snowfall: O in. O in. O in.

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