THIS AVALANCHE ADVISORY EXPIRED ON January 30, 2015 @ 6:37 am
Avalanche Advisory published on January 29, 2015 @ 6:37 am
Issued by Andy Anderson - Tahoe National Forest

The avalanche danger should remain LOW today on all aspects and elevations. LOW danger does not mean no danger and unlikely does not mean impossible. Some small, shallow, isolated areas of unstable snow could linger on isolated terrain features in the form of small wind slabs or loose snow sluffs. Continue to practice safe travel habits and thoughtful decision making when traveling in the backcountry.

1. Low

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Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Normal Caution
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Even though some signs of instability exist involving Tuesday's new snow, the meager amounts of new snow, the scouring caused by yesterday's E and NE winds, and the isolated nature of the instabilities mean that significant avalanche activity will remain unlikely today. Unlikely does not mean impossible. Some small, shallow, and scarce wind slabs may still linger on isolated terrain features in areas that typically experience the most wind loading but did not get scoured yesterday especially in areas south of Highway 50 where more snow fell. These should not extend very far down slope nor should they be very deep or widespread. Additionally some minor sluffing involving the new snow may continue to occur on steep slopes, but these sluffs should remain small and isolated. Overall these small, isolated, and unlikely issues should not pose much hazard to backcountry travelers unless they occur in areas that magnify the consequences of any size avalanche or where any stumble or fall can have serious consequences. These kind of places include steep couliors, slopes above cliffs, and other complex or extreme terrain.

recent observations

Yesterday observations in the Elephant's Back area near Carson Pass showed 2-3 inches of soft light snow resting on top of frozen crusts in most areas. Moderate east and northeast winds scoured the above treeline east and northeast aspects, re-exposing the frozen crusts in those areas. Most data indicated that Tuesday's light snow had bonded well to the old snow surfaces and that it exhibited few slab characteristics. Some small isolated wind slabs up to 6 inches in depth that only extended 1-3 ft down slope did exist on some small isolated terrain features. Some of these minor wind slabs fractured under the weight of a skier, and others did not. In non-wind affected areas, ski cuts on some steep test slopes did trigger minor sluffs that involved the 2-3 inches of soft snow above the crusts. 

Weather and CURRENT CONDITIONS
weather summary

Unsettled weather should remain over the region through Friday due to weak low pressure centered over southern CA. Periods of scattered and broken cloud cover today and tomorrow will represent the main impacts of this system. The forecast calls for the east and northeast winds to diminish today before increasing again tomorrow afternoon as this system moves farther south and east. Daytime highs should remain slightly warmer than normal but still only reach into the mid to upper 30's above 8000 ft and upper 30's to low 40's between 7000 and 8000 ft.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 24 to 31 deg. F.
Max. temperature in the last 24 hours: 39 to 42 deg. F.
Average wind direction during the last 24 hours: East and northeast
Average wind speed during the last 24 hours: 20 to 25 mph
Maximum wind gust in the last 24 hours: 44 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 24 to 33 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Thursday Thursday Night Friday
Weather: Mostly sunny to partly cloudy Partly cloudy Partly cloudy
Temperatures: 40 to 46 deg. F. 21 to 28 deg. F. 39 to 45 deg. F.
Wind Direction: Variable Variable East
Wind Speed: Light Light 10 to 15 mph with gusts to 25 mph in the afternoon
Expected snowfall: 0 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Thursday Thursday Night Friday
Weather: Mostly sunny to partly cloudy Partly cloudy Partly cloudy
Temperatures: 32 to 39 deg. F. 20 to 27 deg. F. 32 to 39 deg. F.
Wind Direction: East Variable East
Wind Speed: 10 to 15 mph in the morning becoming light in the afternoon Light 15 to 20 mph with gusts to 35 mph 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.