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 Wednesday, February 14th, 2007 at 6:58 am

The bottom line: Near and above treeline, pockets of MODERATE avalanche danger exist on wind loaded SW-W-NW aspects 35 degrees and steeper. Elsewhere, isolated pockets of MODERATE danger persist near treeline on N-NE-E aspects, 35 degrees and steeper. Below treeline, avalanche danger is LOW. Small human triggered avalanches remain possible today. Natural avalanches are unlikely.

East winds began to blow yesterday and will continue for the next few days. East winds increased overnight and have become strong enough to cause wind transport of snow and subsequent deposition on the leeward side of ridgelines. East winds are expected to decrease this afternoon. Daytime air temperatures are expected to gradually warm over the next few days.

Yesterday, afternoon cloud build up was not strong enough to produce snow showers. No new snow fell on the forecast area for the first time in the past week. Increasing layer bond strength was observed at all heights of the snowpack yesterday. Easy compression and shear failure was observed within the top foot of the snowpack in a variety of locations, but with increased strength over the pervious day. This weakness still allowed skier triggered sluff activity to occur in steep terrain on recently wind loaded NE aspects. Increasing east winds this morning are expected to scour snow from the upper portion of N-NE-E aspect avalanche start zones today. This will reduce the potential for surface snowpack instability above treeline on N-NE-E aspects. Pockets of surface instability will remain in more sheltered near treeline areas on slopes 35 degrees and steeper that received some wind loading during the past storm cycle. Light to moderate wind loading on SW-W-NW aspects today will create shallow wind slabs that may fail in response to human triggering, especially in cross loaded gullies. Avalanche activity near and above treeline is expected to be limited to within the top 1 foot of the snowpack. Avalanche activity is not expected below treeline.

The bottom line: Near and above treeline, pockets of MODERATE avalanche danger exist on wind loaded SW-W-NW aspects 35 degrees and steeper. Elsewhere, isolated pockets of MODERATE danger persist near treeline on N-NE-E aspects, 35 degrees and steeper. Below treeline, avalanche danger is LOW. Small human triggered avalanches remain possible today. Natural avalanches are unlikely.

At this time, we have not raised enough money to meet our operating budget for this year. If you use this service with any regularity and would like to continue to do so, please show your support for the Sierra Avalanche Center. You may make a tax deductible donation directly to us via Paypal or by sending a check to our address listed above, c/o the Truckee Ranger Station. A financial graph showing the current fundraising and budget numbers is available by clicking here. The financial support already received this winter from a variety of users is greatly appreciated.

Brandon Schwartz, Avalanche Forecaster

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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: 30 deg. F
Average wind direction at Sierra Crest past 24 hours: easterly
Average wind speed at Sierra Crest past 24 hours: 25 mph
Maximum wind gust at Sierra Crest past 24 hours: 48 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 58 inches

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Mountain Weather Forecast For Today:
Sunny skies.
Temperature forecast for 8,000 to 9,000 feet: 31 - 36 deg. F
Ridgetop winds forecast for the Sierra Crest: Easterly 20 - 35 mph, gusting to 45 mph
Snowfall expected in the next 24 hours: 0 inches

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2 Day Mountain Weather Forecast:
7000 to 8000 Feet
Today, sunny skies with daytime highs 36 to 41 degrees F. East winds at 10 to 20 mph. Tonight, partly cloudy with lows 25 to 30 degrees F. Northeast winds at 10 to 20 mph. Thursday, partly cloudy skies with daytime highs 41 to 46 degrees F. Northeast winds at 10 to 20 mph are expected.

Above 8000 Feet
Today, sunny skies with daytime highs 31 to 36 degrees F. East winds at 20 to 35 mph, gusting to 45 mph. Tonight, partly cloudy with lows 24 to 29 degrees F. Northeast winds at 20 to 30 mph. Thursday, partly cloudy skies with daytime highs 36 to 41 degrees F. Northeast winds at 25 to 35 mph are expected.

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.