THIS AVALANCHE ADVISORY EXPIRED ON January 22, 2015 @ 6:43 am
Avalanche Advisory published on January 21, 2015 @ 6:43 am
Issued by Andy Anderson - Tahoe National Forest

The avalanche danger remains LOW on all elevations and aspects. If any wet snow instabilities do form today, they should remain small and isolated. 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

Any wet snow that formed during the day yesterday should have refrozen last night due to clear night time skies and overnight temperatures below freezing. This strong overnight refreeze combined with light east winds, slightly cooler daytime highs, and a snowpack with well established drainage channels will make it difficult for the weak January sun to create enough wet snow for significant wet snow instabilities to form today. If any wet snow issues do arise today, they should remain small and isolated. Even though today's warming may not provide enough melting for significant wet snow instabilities to form, some soft wet surface snow should form on the sun-exposed SE-S-SW aspects. Northerly aspects should remain frozen and firm today.

While avalanche activity will remain unlikely today, other hazards including icy conditions and a shallow snowpack with lots of obstacles remain.

recent observations

Yesterday snow surfaces around Yuba Pass remained frozen on the northerly aspects and on shaded slopes. By midday some softer corn snow did start to form on the SE-S-SW aspects that received direct sunshine. Wet surface snow up to 2 inches deep formed on some of these slopes by noon, but observations up to that point did not reveal any signs of wet snow instabilities. On the northerly aspects, a softer layer of snow does still exist under the thick strong rain/melt-freeze crust on the surface. Observations targeting this softer layer showed that it has become cohesive and seems to have bonded well to itself and the snow around it.  

Weather and CURRENT CONDITIONS
weather summary

Winds shifted to the east and increased yesterday afternoon and evening as the small disturbance that brought some clouds to the area yesterday moved eastward. Skies cleared up yesterday afternoon and remained clear overnight allowing temperatures to fall into the 20's during the night. The winds should continue today under clear and sunny skies as a high pressure ridge starts to move towards the region. The forecast calls for daytime highs in the mid 30's to low 40's in the mountains. Temperatures should climb slightly higher tomorrow as warmer weather moves into the region. Some clouds may also form tomorrow afternoon due to a weak low pressure moving through the area. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 21 to 28 deg. F.
Max. temperature in the last 24 hours: 37 to 44 deg. F.
Average wind direction during the last 24 hours: East to northeast
Average wind speed during the last 24 hours: 10 to 20 mph
Maximum wind gust in the last 24 hours: 40 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 23 to 33 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Wednesday Wednesday Night Thursday
Weather: Sunny Clear Partly cloudy
Temperatures: 35 to 42 deg. F. 20 to 26 deg. F. 40 to 47 deg. F.
Wind Direction: East Variable Variable
Wind Speed: 10 to 15 mph Light Light
Expected snowfall: 0 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Wednesday Wednesday Night Thursday
Weather: Sunny Clear Partly cloudy
Temperatures: 33 to 40 deg. F. 17 to 24 deg. F. 37 to 44 deg. F.
Wind Direction: East Southeast West
Wind Speed: 10 to 15 mph with gusts to 25 mph 10 to 15 mph in the evening becoming light overnight Light in the morning increasing to 10 to 15 mph with gusts to 25 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.