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 12, 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.

A small system should move through the forecast area today. This weak system has little moisture associated with it. If it brings any snow, it should only bring a trace of new snow above 6000'. A strong high pressure ridge follows this storm bringing sunny, warm weather to the forecast area. The winds should shift to the north and east as the high pressure moves in. The forecast calls for the winds to be moderate and then become light by tomorrow afternoon
Observations submitted and made yesterday indicate that the rain event affected most of the crest up to 9000'. A hard, icy 1/2" (1.5cm) rain crust caps the snow surface on most aspects. In some areas the crust supports a person's weight in other areas it does not making it a sometimes breakable, sometimes supportable crust. Even though the air temperatures only reached the low end of the forecast range yesterday, the combination of these warmer air temps and the sun did manage to soften this crust by mid-afternoon on ESE-SE-S-SW aspects below 8000'. The snow surface should have refrozen again last night due to overnight lows in the mid 20's. Today's cloud cover and slightly lower temperatures should keep the crust and snow surface frozen longer. In the Mount Rose area where there was no rain event a breakable crust or very heavy snow exists on most aspects. Stability tests and other observations continue to indicate that the snowpack is gaining strength below the surface. Due to the overnight refreeze, the forecast cloud cover, slightly lower forecast temperatures, and shortness of daylight hours wet snow instabilities should be unlikely. If they do occur today they should be limited to the surface layer of the snow and should be small and isolated.

Natural and human triggered avalanche activity is unlikely today. If the temperatures climb higher than expected or the precipitation that falls today is rain instead of snow some wet snow instabilities could form today. Remember LOW avalanche danger does not mean NO avalanche danger. The avalanche process does not simply turn off. Very, isolated pockets of instability may exist on any LOW danger day.

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): 22 deg. F
Max. temperature at Sierra Crest past 24 hours: 29 deg. F
Average wind direction at Sierra Crest past 24 hours: West
Average wind speed at Sierra Crest past 24 hours: 22 mph
Maximum wind gust at Sierra Crest past 24 hours: 45 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 59 inches
Mountain Weather Forecast For Today:
Mostly cloudy today with a chance of snow above 6000 feet.
Temperature forecast for 8,000 to 9,000 feet: 30 to 36 deg. F
Ridgetop winds forecast for the Sierra Crest: West at 15 to 20 mph with gusts to 35 mph shifting to the north in the afternoon.
Snowfall expected in the next 24 hours: trace
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, mostly cloudy with a chance of snow with only a trace of accumulation. Daytime highs 34 to 40 deg. F. West winds at 10 to 15 mph shifting to the northwest this afternoon.

Tonight, partly cloudy skies in the evening then clearing. Overnight lows 22 to 28 deg. F. Light winds shifting to to the southeast at 10 mph after midnight.

For Sunday, sunny and warm with daytime highs 39 to 43 deg. F. Southeast winds at 10 mph decreasing in the afternoon.

Above 8000 Feet:
Today, mostly cloudy with a chance of snow with only a trace of accumulation. Daytime highs 30 to 36 deg. F. West winds at 15 to 20 mph shifting to the north this afternoon with gusts to 35 mph.

Tonight, partly cloudy skies in the evening then clearing. Overnight lows 25 to 29 deg. F. North winds shifting to to the east at 10 mph after midnight.

For Sunday, sunny and warm with daytime highs 37 to 43 deg. F. East winds at 10 mph decreasing in the afternoon.

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