THIS AVALANCHE ADVISORY EXPIRED ON January 28, 2017 @ 6:45 am
Avalanche Advisory published on January 27, 2017 @ 6:45 am
Issued by Steve Reynaud - Tahoe National Forest

Moderate avalanche danger will continue due to potential wind slab development.  These wind slabs will be possible in near treeline and above treeline terrain on slopes steeper than 35 degrees.  Low avalanche danger continues in all below treeline terrain.  Identify and avoid areas where wind slabs may exist.

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

Wind slabs will be possible on S-SW-W-NW-N aspects in near treeline and above treeline terrain.  E winds have been in the strong range with gale force gusts starting yesterday afternoon and through the evening above 8000'.  E winds are forecasted to continue today but will begin to decrease into the afternoon. 

Look for blowing snow, cornice formation, wind pillows, and snow surface scouring as clues to where wind slabs may exist.  Pay attention to gully features that may have been cross loaded by the recent E winds.

recent observations

Observations were made and received from Mt. Rose and from Flagpole Peak (Echo Summit area).  Both areas showed a right side up snowpack that has continued to consolidate and settle.  Both areas also had wind scouring and wind transport from the previous W winds.  On Mt. Rose, small wind slabs and cornices were developed on NE-E-SE aspects.  Large cornice chucks were dropped onto test slopes with no signs of cohesive wind slabs present.  At both locations, the current NE/E winds were not strong enough at the time to transport snow although plenty of low density surface snow still existed for wind transport.  Sun crusts and denser surface snow was observed on slopes receiving sun over the last couple days.

Weather and CURRENT CONDITIONS
weather summary

Strong high pressure will continue over the west coast through Monday with warming conditions and valley inversions.  Generally light winds at the lower elevations with cold E winds above 8000'.  These E winds have been in the strong to gale force range overnight and should decrease this afternoon.  A return to unsettled weather is expected by Wednesday of this next week. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 13 deg. F.
Max. temperature in the last 24 hours: 31 deg. F.
Average wind direction during the last 24 hours: E
Average wind speed during the last 24 hours: 40 to 50 mph
Maximum wind gust in the last 24 hours: 105 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 113 to 136 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Friday Friday Night Saturday
Weather: Sunny Clear. Sunny.
Temperatures: 30 to 35 deg. F. 9 to 19 deg. F. 33 to 38 deg. F.
Wind Direction:
Wind Speed: Light winds. Light winds. Light winds.
Expected snowfall: 0 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Friday Friday Night Saturday
Weather: Sunny. Clear. Sunny.
Temperatures: 31 to 36 deg. F. 19 to 27 deg. F. 33 to 38 deg. F.
Wind Direction: E E E
Wind Speed: 15 to 20mph. Gusts up to 50mph decreasing to 40mph in the afternoon. 10 to 15mph with gust to 25mph. Light winds. Gusts up to 25mph in the afternoon.
Expected snowfall: 0 in. 0 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.

For a recorded version of the Avalanche Advisory call (530) 587-3558 x258