THIS AVALANCHE ADVISORY EXPIRED ON December 15, 2014 @ 6:30 am
Avalanche Advisory published on December 14, 2014 @ 6:30 am
Issued by Brandon Schwartz - Tahoe National Forest

Near and above treeline, pockets of MODERATE danger continue to exist along the Sierra Crest on NW-N-NE-E-SE aspects on slopes 35 degrees and steeper due to lingering wind slabs. For all other areas, avalanche danger is LOW.

2. Moderate

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Above Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

2. Moderate

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Near Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
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    Historic
    Very Large
    Large
    Small

Much like yesterday, pockets of unstable wind slab are expected to continue to linger mainly along the Sierra Crest in near and above treeline terrain on NW-N-NE-E-SE aspects. Pockets of instability will exist within surrounding areas of seemingly stable snow. Traveling on thin portions of the slab near trigger points such as exposed rocks or on slopes previously undercut by ski/snowmobile tracks will increase the likelihood of triggering an avalanche. Very little evidence of instability is expected to exist in the backcountry today. Once again, do not allow a lack of instability clues to lead to lazy or half hearted backcounty travel techniques. Anyone triggering an avalanche today will most likely be taken by surprise. Act like a pro by traveling one at time in avalanche terrain and moving from one high quality island of safety to the next.

recent observations

A skier triggered wind slab avalanche occurred yesterday near Elephant's Back in the Carson Pass area on an NE aspect around 8,900' in near treeline terrain on a 40 degree slope. The crown measured less than 1 foot deep, approximately 120' wide and ran approximately 270' down slope. The avalanche was triggered in an area of exposed rocks by the second skier to descend the slope. The slope had been previously undercut by a traversing skin track about 100' below (photo, more info). The use of one at a time travel by this party despite a perception of stable conditions helped to keep any consequences to a minimum.

Recent observations from around the forecast area tend to point towards stable snowpack conditions. Occasional outliers of isolated avalanche activity and isolated cracking in previously undercut areas are the reminder that unstable wind slabs are still out there. The take home message is that pockets of instability exist within larger surrounding areas of stable snow. Manage terrain accordingly.

Weather and CURRENT CONDITIONS
weather summary

A series of weak weather systems will move through the region over the next several days. For today, expect increasing cloud cover with a slight chance of light snow showers during the afternoon hours. Little to no new snow accumulation is expected. Remote sensors are reporting air temperatures between 8,000' and 9,000' in the mid teens this morning. Ridgetop winds are light out of the southwest. As the day progresses, maximum daytime air temperatures are forecast to reach the mid 20s to mid 30s for areas above 7,000'. Ridgetop winds are forecast to increase to light to moderate in speed with gusts to 25 mph. Chances for accumulating snowfall increase on Monday. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 14 to 18 deg. F.
Max. temperature in the last 24 hours: 23 to 36 deg. F.
Average wind direction during the last 24 hours: Southwest
Average wind speed during the last 24 hours: 8 mph
Maximum wind gust in the last 24 hours: 19 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 22 to 36 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy skies with a slight chance of snow showers in the afternoon. Mostly cloudy skies with a slight chance of snow showers. Cloudy skies with snow likely.
Temperatures: 27 to 34 deg. F. 17 to 24 deg. F. 25 to 32 deg. F.
Wind Direction: SW SW SE
Wind Speed: Light winds Light winds 10 to 15 mph, increasing to 20 to 25 mph with gusts to 35 mph in the afternoon.
Expected snowfall: 0 to trace in. 0 to trace in. Up to 3 in.
For 8000 ft. to 9000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy skies with a slight chance of snow showers in the afternoon. Mostly cloudy skies with a slight chance of snow showers. Cloudy skies with snow likely.
Temperatures: 25 to 32 deg. F. 17 to 24 deg. F. 22 to 29 deg. F.
Wind Direction: SW SW S
Wind Speed: 10 to 15 mph with gusts to 25 mph. 10 to 15 mph with gusts to 25 mph in the evening, becoming light. 20 to 25 mph with gusts to 35 mph, increasing to 30 to 35 mph with gusts to 55 mph in the afternoon.
Expected snowfall: 0 to trace in. 0 to trace in. Up to 3 in.
Disclaimer

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.