THIS AVALANCHE FORECAST EXPIRED ON January 17, 2017 @ 6:59 am
Avalanche Forecast published on January 16, 2017 @ 6:59 am
Issued by Andy Anderson - Tahoe National Forest

LOW avalanche danger exists at all elevations. While triggering an avalanche has become unlikely, some unstable snow may still exist on isolated terrain features and small avalanches could still occur in isolated or extreme terrain. Continue to evaluate the terrain and snowpack while traveling in the backcountry to identify where these isolated areas of unstable snow may still exist.

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 ?

Overall data and observations have shown a well-bonded, consolidated snowpack across the forecast area. Triggering an avalanche has become unlikely. Unlikely does not mean impossible, and some unstable snow could still exist on isolated terrain features. Steep, complex, and extreme terrain and unsupported slopes like couloirs, cliffy areas, or hanging snowfields represent the best places to find these isolated areas of instability where a person may still encounter a lingering avalanche issue like a wind slab or a cornice failure. Large cornices that could break under the weight of a person still exist along many ridgelines. Despite the low avalanche danger, continue to practice appropriate backcountry travel techniques like regrouping in safe areas out of avalanche terrain and only having one person on a slope at a time. 

recent observations

Observations on Becker Ridge (Echo Summit) and Castle/Andesite (Donner Summit) showed variable snow conditions with wind scoured and firm wind-packed surfaces on exposed near and above treeline slopes and softer cold snow remaining on sheltered northerly aspects in near and below treeline terrain. On the sun exposed aspects in both areas, thin sun crusts or wet snow had formed on the surface. Surface hoar that persisted into the afternoon in shady areas had also formed on open slopes. Snowpit tests and observations in these areas showed a strengthening snowpack with good bonding within and between the layers. On Castle Peak, ski kicks could still break cornices, but those cornice pieces did not trigger any other signs of instabilities. At lower elevations near Little Truckee Summit below the inversion layer, cool cloudy conditions existed. Snow surfaces remained soft and cold on the northerly aspects. Snowpit data did reveal some facets near the Jan. 12th rain crust that exists in some areas below 7500 ft, but tests did not show signs of instability on this layer at this time.

Weather and CURRENT CONDITIONS
weather summary

The east and northeast winds increased along the ridgetops during the night, but they should decrease again today. Expect slightly warmer temperatures today with daytime highs in the mid to upper 30's above 7000 ft. and into the low 40's above 8000 ft. The inversion should persist with a cloud deck below 7500 ft. and sunny warmer weather above 7500 ft. Tomorrow brings more of the same weather with slightly warmer daytime highs as the winds shift to the south. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 17 to 26 deg. F.
Max. temperature in the last 24 hours: 36 to 45 deg. F.
Average wind direction during the last 24 hours: East and northeast
Average wind speed during the last 24 hours: Before midnight: 10 mph | After midnight: 35 mph
Maximum wind gust in the last 24 hours: 55 to 70 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 79 to 107 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy Partly cloudy Partly cloudy
Temperatures: 33 to 38 deg. F. 12 to 22 deg. F. 38 to 43 deg. F.
Winds: Variable Variable South
Expected snowfall: 0 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy Partly cloudy Partly cloudy
Temperatures: 34 to 40 deg. F. 16 to 22 deg. F. 37 to 42 deg. F.
Winds: Northeast Northeast shifting to the west after midnight Northeast shifting to the south 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