THIS AVALANCHE ADVISORY EXPIRED ON January 26, 2017 @ 6:45 am
Avalanche Advisory published on January 25, 2017 @ 6:45 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger exists in near treeline and above treeline areas on slopes 35 degrees and steeper due to the possibility of another round of wind slab development. LOW avalanche danger exists for wind protected areas below treeline.

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
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Ridgetop winds have shifted back to the WSW and are strong enough to move snow this morning. Plenty of low density recent storm snow is available for wind transport. New wind slab development is possible today in near treeline and above treeline areas mainly on NW-N-NE-E-SE-S aspects. Wind slabs could form in isolated areas on SW-W aspects as well.

Look for areas of blowing snow, new snow surface scouring, and new cornice formation to determine where new wind slabs are likely to exist.

recent observations

Observations made yesterday on Trimmer Peak (Luther Pass area) and on Frog Lake Ridge (Carson Pass area) indicated improving stability within the recent storm snow. In both areas the top 6 to 8 inches of recent storm snow was very low density and available on all aspects for wind transport. The moderate speed NE winds that occurred in some areas yesterday were notably absent on Trimmer Peak and Frog Lake Ridge. No signs of problematic wind slabs were observed in either area. Large cornices exist along many ridgelines. Deep tree wells were noted on Trimmer Peak.

Weather and CURRENT CONDITIONS
weather summary

Sunny skies this morning will give way to increasing cloud cover this afternoon as a weak weather disturbance approaches the region. Light snow showers could begin this afternoon. Showers are forecast to continue through tomorrow. Little to no new snow accumulation is expected. Ridgetop winds have shifted back to the WSW this morning ahead of the approaching weather system. Light to moderate wind speeds are forecast for today and tonight, eventually becoming light tomorrow afternoon.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 2 to 13 deg. F.
Max. temperature in the last 24 hours: 14 to 26 deg. F.
Average wind direction during the last 24 hours: NE
Average wind speed during the last 24 hours: 21 mph
Maximum wind gust in the last 24 hours: 40 mph
New snowfall in the last 24 hours: 0 to trace inches
Total snow depth: 119 to 141 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Wednesday Wednesday Night Thursday
Weather: Partly cloudy skies, becoming mostly cloudy. Isolated snow showers in the afternoon. Mostly cloudy skies. Scattered snow showers in the evening. Isolated snow showers after midnight. Mostly cloudy skies becoming cloudy. Slight chance of snow showers in the morning. A chance of snow showers in the afternoon.
Temperatures: 25 to 30 deg. F. 5 to 15 deg. F. 25 to 30 deg. F.
Wind Direction: WSW SW SW
Wind Speed: Light winds. Gusts up to 25 mph in the morning. Light winds Light winds
Expected snowfall: 0 to trace in. 0 to trace in. 0 to trace in.
For 8000 ft. to 9000 ft.
Wednesday Wednesday Night Thursday
Weather: Partly cloudy skies, becoming mostly cloudy. Isolated snow showers in the afternoon. Mostly cloudy skies. Scattered snow showers in the evening. Isolated snow showers after midnight. Mostly cloudy skies becoming cloudy. Slight chance of snow showers in the morning. A chance of snow showers in the afternoon.
Temperatures: 22 to 28 deg. F. 9 to 14 deg. F. 22 to 28 deg. F.
Wind Direction: WSW SW SW
Wind Speed: 15 to 20 mph with gusts to 40 mph. 10 to 15 mph with gusts to 30 mph. 10 to 15 mph with gusts to 25 mph in the morning, becoming light.
Expected snowfall: 0 to trace in. 0 to trace in. 0 to trace 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