THIS AVALANCHE ADVISORY EXPIRED ON February 19, 2014 @ 7:00 am
Avalanche Advisory published on February 18, 2014 @ 7:00 am
Issued by Andy Anderson - Tahoe National Forest

Near and above treeline pockets of MODERATE avalanche danger still exist on wind loaded slopes 35 degrees and steeper on NW-N-NE-E-SE aspects due to lingering wind slabs. In wind protected areas below treeline and in wind scoured areas near and above treeline, avalanche danger remains 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

Most of the wind slabs that still exist on on the leeward NW-N-NE-E-SE aspects remain relatively small and difficult to trigger. However, some wind slabs 1-2 ft in depth still linger in the most heavily wind loaded areas that received the most snow on Saturday night. Complex and/or extreme terrain including "cliffy" areas, unsupported slopes, couliors, etc represent the most likely places to find these pockets of larger more fragile wind slabs where human triggered wind slab avalanches will remain possible today.

recent observations

Strong winds continued to move snow from the windward aspects to the leeward aspects near the ridgelines in the Mt. Rose and Carson Pass areas yesterday. Wind slabs up to 16 inches deep existed on leeward aspects in both of those areas. On Red Lake Peak observations and snowpit data collected near the avalanche that occurred on 2/16 showed that the wind slabs in that steep and complex wind loaded terrain remain fragile and susceptible to human triggering. On Incline Lake Peak and on Tamarack Peak data indicated that the wind slabs remain more difficult to trigger. On Tamarack Peak ski cuts on unsupported/undercut test slopes that held those wind slabs did cause them to fail. On similar supported/non-undercut test slopes ski cuts did not cause any cracks or failures.

Weather and CURRENT CONDITIONS
weather summary

The forecast calls for another dry warm day. The winds decreased yesterday afternoon and should remain light to moderate through today. Some high clouds should remain over the area today as well. By this afternoon and evening the winds and cloud cover should begin to increase as a small cold front moves into the region. For the most part decreased temperatures and those increased clouds and stronger winds should represent the only impacts of this front. However, there is a chance for some scattered snow showers from I80 north tonight and tomorrow morning. By mid-morning tomorrow skies should begin to clear and the winds should begin to shift to the northwest. Expect daytime highs tomorrow 5-7 degrees cooler than today's. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 23 to 32 deg. F.
Max. temperature in the last 24 hours: 36 to 42 deg. F.
Average wind direction during the last 24 hours: Southwest
Average wind speed during the last 24 hours: 20 to 25 mph
Maximum wind gust in the last 24 hours: 49 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 38 to 48 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy Partly cloudy becoming mostly cloudy with scattered snow showers after midnight Scattered snow showers in the morning becoming partly cloudy by midday.
Temperatures: 41 to 47 deg. F. 24 to 29 deg. F. 35 to 40 deg. F.
Wind Direction: Southwest Southwest West shifting to the northwest in the afternoon
Wind Speed: 5 to 15 mph in the morning increasing to 10 to 20 mph with gusts to 35 mph in the afternoon 20 to 30 mph with gusts to 40 mph increasing to to 25 to 35 mph with gusts to 55 mph after midnight 25 to 40 mph with gusts to 60 mph decreasing to 15 to 25 mph with gusts to 35 mph in the afternoon
Expected snowfall: 0 in. 0 to 1 in. 0 in.
For 8000 ft. to 9000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy Partly cloudy becoming mostly cloudy with scattered snow showers after midnight Scattered snow showers in the morning becoming partly cloudy by midday.
Temperatures: 34 to 40 deg. F. 21 to 26 deg. F. 28 to 35 deg. F.
Wind Direction: Southwest Southwest Southwest shifting to northwest in the afternoon
Wind Speed: 15 to 25 mph with gusts to 35 mph increasing to 20 to 35 mph with gusts to 60 mph in the afternoon 35 to 45 mph with gusts to 65 mph increasing to 50 to 60 mph with gusts to 90 mph after midnight 55 to 65 mph with gusts to 95 mph decreasing to 30 to 40 mph with gusts to 70 mph in the afternoon
Expected snowfall: 0 in. 0 to 1 in. 0 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.