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 15, 2008 6:57 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:

This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE avalanche danger will develop on SE-S-SW-W aspects, 37 degrees and steeper in response to daytime warming.

High pressure has built in over the forecast area with sunny skies and warm air temperatures expected over the next several days. Air temperatures today are expected to warm above freezing at all elevations. This follows a 36 hour period of below freezing air temperatures in all areas over 6,500'. East winds remain moderate to strong over the Sierra Crest this morning, but are expected to decrease significantly by mid day.

Rapidly warming air temperatures will melt surface snow in sun exposed areas today. As daytime warming causes free water to form within the surface snow, areas of wet snow instability are expected to develop on steep SE-S-SW-W aspects. On northerly aspects, a very well bonded snowpack structure has been observed throughout the forecast area over the past 10 days. Snow surface conditions on northerly aspects are wind scoured above treeline. Some pockets of unconsolidated surface snow exist in the most shaded and wind sheltered areas below treeline. The snow surface is expected to remain cold today on shaded northerly aspects due to the lower sun angle of February when compared to mid March or April.

As wet snow develops on steep SE-S-SW-W aspects today, shallow loose snow type avalanche activity will become possible in response to human triggering. Natural avalanche activity that is large enough to present a significant hazard to backcountry travelers in unlikely today. On northerly aspects where the snowpack has remained cold, natural and human triggered avalanche activity is unlikely.

The bottom line: This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE avalanche danger will develop on SE-S-SW-W aspects, 37 degrees and steeper in response to daytime warming.

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): 17 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: 58 mph
Maximum wind gust at Sierra Crest past 24 hours: 87 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 82 inches

Mountain Weather Forecast For Today:
Sunny skies with a warming air trend.
Temperature forecast for 8,000 to 9,000 feet: 38 to 41 deg. F
Ridgetop winds forecast for the Sierra Crest: East at 45 to 60 mph with gusts to 70 mph, decreasing to 15 to 25 mph with gusts to 35 mph in the afternoon.
Snowfall expected in the next 24 hours: 0 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, sunny skies with daytime highs around 43 deg. F. East winds at 10 to 15 mph with gusts to 25 mph in the morning.

Tonight, clear skies with overnight lows 19 to 29 deg. F. East winds around 10 mph in the evening, becoming light.

For Saturday, sunny skies with daytime highs around 52 deg. F. Light winds.

Above 8000 Feet:
Today, sunny skies with daytime highs around 40 deg. F. East winds at 15 to 25 mph with gusts to 55 mph, decreasing to gusts to 35 mph in the afternoon.

Tonight, clear skies with overnight lows 23 to 31 deg. F. Northeast winds around 10 mph.

For Saturday, sunny skies with daytime highs 43 to 49 deg. F. North winds at 10 mph shifting to east winds up to 10 mph 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:
	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.