THIS AVALANCHE ADVISORY EXPIRED ON February 27, 2017 @ 6:45 am
Avalanche Advisory published on February 26, 2017 @ 6:45 am
Issued by Steve Reynaud - Tahoe National Forest

Moderate avalanche danger continues today due to a wind slab avalanche problem.  These wind slabs exist in near treeline and above treeline terrain.  Human triggered avalanches remain possible today.  Low avalanche danger continues in below treeline areas. 

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
  • Size ?
    Historic
    Very Large
    Large
    Small

Human triggered wind slab avalanches remain possible on NW-N-NE-E-SE aspects.  Increasing SW winds throughout today will continue to build and create new wind slabs in near and above treeline areas.  Look for blowing snow, cornice formation, and wind pillows.  Avoid steep wind loaded terrain that is being actively wind loaded.

recent observations

Observations were made and received from Incline Lake Peak (Mt. Rose area), Jakes Peak (West Shore area), National Geo Bowl (Squaw Valley area), The Nipple (Carson Pass area), Donner Ridge (Donner Summit area), and Fireplug (Mt. Rose area).  Avalanches were reported from Fireplug, Incline Lake Peak, and National Geo Bowl.  Most of these were wind slab avalanches with a storm slab reported from Fireplug.  All of these avalanches were 1 foot deep or less failing within the recent storm snow.  Minor loose dry sluffing was reported from Donner Summit, West Shore, and Carson Pass areas with no additional signs of instabilities.  Most observations reported previous wind scouring and wind slab development.  Areas saw partly cloudy to mostly cloudy conditions with some long sun breaks throughout the day.  Wet snow and sun crusts were reported on E-SE-S-SW aspects by the afternoon.

Weather and CURRENT CONDITIONS
weather summary

A weak low pressure system will bring gusty winds this afternoon and evening with light snow tonight into Monday.  2 to 6'' of snow is forecasted for the Tahoe Basin with up to 8'' west of Hwy. 89.  Light snow flurries with a cold NW flow will continue through Tuesday before high pressure builds into the area midweek with warming temperatures.  A winter weather advisory is in effect from 7pm this evening to 10am Monday morning.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 10 to 20 deg. F.
Max. temperature in the last 24 hours: 31 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 15 to 35 mph
Maximum wind gust in the last 24 hours: 40 mph
New snowfall in the last 24 hours: Trace inches
Total snow depth: 140 to 190 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Sunday Sunday Night Monday
Weather: Partly cloudy then becoming mostly cloudy. Slight chance of snow in the afternoon. Cloudy. Snow likely in the evening then snow after midnight. Mostly cloudy. Snow showers likely in the morning then chance of snow showers in the afternoon.
Temperatures: 26 to 31 deg. F. 14 to 19 deg. F. 24 to 29 deg. F.
Wind Direction: SW SW W
Wind Speed: Light winds becoming 20 to 30mph with gusts to 60mph in the afternoon. 20 to 30mph with gusts to 60mph. 10 to 15mph. Gusts to 40mph decreasing to 30mph in the afternoon.
Expected snowfall: 0 in. 2 to 5 in. Up to 2 in.
For 8000 ft. to 9000 ft.
Sunday Sunday Night Monday
Weather: Partly cloudy then becoming mostly cloudy. Slight chance of snow in the afternoon. Cloudy. Snow likely in the evening then snow after midnight. Mostly cloudy. Snow showers likely in the morning then chance of snow showers in the afternoon.
Temperatures: 23 to 28 deg. F. 11 to 16 deg. F. 20 to 26 deg. F.
Wind Direction: SW SW W
Wind Speed: 10 to 15mph with gusts to 40mph increasing to 30 to 45mph with gusts to 85mph in the afternoon. 30 to 45mph with gusts to 85mph. 15 to 25mph. Gusts up to 65mph decreasing to 40mph in the afternoon.
Expected snowfall: 0 in. 2 to 5 in. Up to 2 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