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 8, 2008 6:53 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:
Near and above treeline, avalanche danger is CONSIDERABLE on N-NE-E aspects, 35 degrees and steeper. Below treeline, avalanche danger is MODERATE in open areas 37 degrees and steeper.

Another storm system is beginning to impact the forecast area this morning. Air temperatures at the upper elevations have remained in the teens for the past few days, but are expected to climb into the upper 20s today as warm air arrives ahead of the approaching storm system. Southwest winds have been moderate to strong over the ridges for the past several days and will continue through tonight.
Areas of snowpack instability continue to exist within the forecast area. Moderate to strong southwest winds have continued to wind load N-NE-E aspect avalanche start zones over the past few days. This has occurred despite only light new snowfall amounts. These areas of instability have varied greatly by region. Yesterday, widespread human triggering avalanches was reported along the ridge between Jobs Peak and the boundary of Heavenly Ski Area. Wind loaded areas on N-NE-E aspects above treeline failed easily under the weight of a skier. These avalanches created crowns up to 18 inches deep, occurring within the wind transported snow and were large enough to possibly injure, but not bury a person. On Tamarack Peak in the Mount Rose area, less instability was observed. Some isolated shooting cracks were observed near and above treeline at the north end of the Proletariat Face, again occurring within the recently wind loaded snow. Snowpit data taken from north and east aspects in the immediate area showed stable test results below the top 1 foot of the snowpack. No new avalanche activity was observed in this area.

Another 8 to 12 inches of new snow is expected to fall on the forecast area today with the greatest snowfall intensity occurring during the afternoon hours. Southwest winds will continue to windload N-NE-E aspects near and above treeline. Human triggered avalanches will remain probable in steep wind loaded areas and natural avalanches will become possible, especially during the afternoon hours. Below treeline, human triggered avalanches are possible in steep open areas. Natural avalanches are unlikely below treeline today.

The bottom line: Near and above treeline, avalanche danger is CONSIDERABLE on N-NE-E aspects, 35 degrees and steeper. Below treeline, avalanche danger is MODERATE in open areas 37 degrees and steeper.
Please send us your snow, weather, and avalanche observations by clicking the submit observations link on our contact page.

Brandon Schwartz, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 13 deg. F
Max. temperature at Sierra Crest past 24 hours: 18 deg. F
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 43 mph
Maximum wind gust at Sierra Crest past 24 hours: 76 mph
New snow fall at 8,200 feet past 24 hours: 0 to trace inches
Total snow depth at 8,200 feet: 60-70 inches
Mountain Weather Forecast For Today:
Becoming cloudy with snow. Heavy at times in the afternoon.
Temperature forecast for 8,000 to 9,000 feet: 26 to 30 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest at 30 to 50 mph with gusts to 90 mph.
Snowfall expected in the next 24 hours: 8 to 12 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, becoming cloudy with snow. Heavy at times in the afternoon. Snow accumulation 7 to 12 inches. Daytime highs near 30 deg. F. Southwest winds at 15 to 25 mph, with gusts to 40 mph.

Tonight, cloudy skies with snow showers, becoming scattered by midnight. Snow accumulation 2 to 4 inches. Overnight lows around 20 deg. F. Southwest winds at 20 to 35 mph with gusts to 50 mph, decreasing to 40 mph after midnight.

For Wednesday, mostly cloudy with a slight chance of snow showers. Daytime highs near 32 deg. F. Southwest winds at 10 to 15 mph with gusts to 25 mph in the morning.

Above 8000 Feet:
Today, becoming cloudy with snow. Heavy at times in the afternoon. Snow accumulation 8 to 12 inches. Daytime highs 26 to 30 deg. F. Southwest winds at 30 to 50 mph, with gusts to 90 mph.

Tonight, cloudy skies with snow showers, becoming scattered by midnight. Snow accumulation 2 to 4 inches. Overnight lows around 18 deg. F. Southwest winds at 30 to 40 mph with gusts to 80 mph, decreasing to 20 to 30 mph with gusts to 60 mph after midnight.

For Wednesday, mostly cloudy with a slight chance of snow showers. Daytime highs 28 to 34 deg. F. West 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:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.