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 February 6, 2008 7:00 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:

This morning the avalanche danger is LOW on all aspects and elevations. Below 9000' on sun exposed slopes steeper than 35 degrees areas of MODERATE danger could develop during the day due to daytime warming.

The winds shifted to the west and southwest late in the day yesterday and increased in intensity due to the influence of a low pressure system north of the forecast area. The combination of a high pressure ridge off the California coast and this west southwest flow should bring even warmer air temperatures to the forecast area today. Another system should pass to the north of us tonight keeping the southwest winds strong. By later this week the high pressure system should be well established bringing a few days of spring-like weather to the area.

Yesterday in the Mount Rose area the northeasterly winds calmed down early in the day. Observers reported some roller ball activity on south facing slopes in the Chocolate Peak area as well as "small slides" in a south facing gully. Another observation from a protected bowl near Twin Peaks (Ward Canyon) reported a point-release sluff on a 35 degree NNE aspect. Observations from Waterhouse Peak near Luther Pass where the east winds did not calm down till later indicated mostly stable snow on all aspects. Today without the moderating influence of the strong, cold northeast winds the warmer air temperatures and direct sunlight should cause instabilities due to increased warming to become more widespread. Recently deposited snow on the W-SW-S-SE aspects should react the most to today's warming.

Human triggered roller balls, pinwheels, and loose point release avalanche activity could become possible on slopes that are exposed directly to the sun and are steeper than 35 degrees today. Some of the E and NW aspects could also start to react if the temperatures reach higher than forecasted or the morning clouds dissipate faster than forecast. Isolated areas where human triggering of a slab avalanche is possible may still exist in steep, cross loaded NW and SE facing gullies that see large amounts of solar radiation today. These areas should be rare but deserve a measure of caution from backcountry travelers today. Natural avalanche activity is unlikely today.
The bottom line: This morning the avalanche danger is LOW on all aspects and elevations. Below 9000' on sun exposed slopes steeper than 35 degrees areas of MODERATE danger could develop during the day due to daytime warming.

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: 34 deg. F
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 30 mph
Maximum wind gust at Sierra Crest past 24 hours: 58 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 93 inches
Mountain Weather Forecast For Today:
Partly cloudy this morning and clearing during the day.
Temperature forecast for 8,000 to 9,000 feet: 30 to 35 deg. F
Ridgetop winds forecast for the Sierra Crest: West at 10 to 20 mph with gusts to 40 mph.
Snowfall expected in the next 24 hours: 0 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, partly cloudy this morning and clearing during the day. Daytime highs 32 to 38 deg. F. West winds at 10 to 20 mph with gusts to 35 mph decreasing in the afternoon.

Tonight, partly cloudy with overnight lows 24 to 28 deg. F. West winds at 10 to 15 mph with gusts to 25 mph.

For Thursday, partly cloudy with daytime highs 37 to 43 deg. F. West winds at 10 to 20 mph with gusts to 40 mph.

Above 8000 Feet:
Today, partly cloudy this morning and clearing during the day. Daytime highs 30 to 35 deg. F. West winds at 20 to 30 mph with gusts to 60 mph shifting to the northwest and decreasing 10 to 20 mph with gusts to 40 mph in the afternoon.

Tonight, partly cloudy with lows 27 to 32 deg. F in the evening and rising to 31 to 37 deg. F after midnight. Northwest winds at 15 to 20 mph with gusts to 30 mph shifting to the west and increasing to 25 to 35 mph with gusts to 50 mph overnight.

For Thursday, partly cloudy with daytime highs in the 30's deg. F. West winds at 35 to 45 mph with gusts to 70 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:
	Wednesday:	Wednesday Night:	Thursday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Wednesday:	Wednesday Night:	Thursday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.