THIS AVALANCHE FORECAST EXPIRED ON April 3, 2018 @ 6:48 am
Avalanche Forecast published on April 2, 2018 @ 6:48 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger will occur at all elevations today as a loose wet avalanche problem develops in response to daytime warming. Evaluate snow surface supportability on an ongoing basis and avoid avalanche terrain in areas where marginally supportable to unsupportable wet snow exists.

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.

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Loose Wet
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As daytime warming progresses, loose wet avalanches will become possible at all elevations on E-SE-S-SW-W aspects. Further into the daytime hours, this loose wet avalanche problem will spread to NW-N-NE aspects as well. Avalanche size up to D2 is possible (large enough to bury or injure a person). Identify and avoid avalanche terrain in areas where natural or human triggered roller balls are occurring and/or marginally supportable to unsupportable wet snow exists.

Skies were clear over the forecast area for the majority of last night and SW winds kept air temperature inversion conditions to a minimum. As a result, a fairly good snow surface refreeze is expected to have occurred overnight. Areas of unstable wet snow will likely be a little slower to form today as compared to the past several days, but will still form by the afternoon hours. Pay close attention to the remaining thickness of surface crust as the day progresses. Once it becomes marginally supportable to unsupportable, the snowpack can quickly become unstable.

recent observations
Submit Observations

* Recent observations from around the forecast area continue to show increasingly well established melt-freeze conditions on E-SE-S-SW-W aspects. The snowpack remains transitional having undergone only very superficial melt-freeze on many NW-N-NE aspects at the upper elevations. Lower elevation NW-N-NE aspects hold fairly well established melt-freeze conditions.

* Snowpit tests performed Sunday on Silver Peak (Pole Creek area) in the crown of one of the numerous deep slab avalanches from March 22 indicated that the associated weak layer continues to retain characteristics that allow for propagation. No signs of current deep slab instability were observed.

Weather and CURRENT CONDITIONS
weather summary

Air temperatures are forecast to be slight colder today as an area of cold air passes by to the E of the forecast area. Some cloud cover of varying thickness is expected today along with moderate speed W winds along the ridgetops. Winds are forecast to go light tonight along with clear skies. Air temperature inversion conditions are expected to set up tonight with the coldest air down on the mountain valley floors and warmer air at the upper elevations. Tuesday will see a sunny start to the day with additional warming at the upper elevations. A warm atmospheric river type storm event is in the forecast for Friday-Saturday.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 29 to 33 deg. F.
Max. temperature: 45 to 50 deg. F.
Average ridgetop wind direction: SW
Average ridgetop wind speed: 32 mph
Maximum ridgetop wind gust: 50 mph
New snowfall: 0 inches
Total snow depth: 66 to 100 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 skies. Clear skies. Sunny skies, becoming partly cloudy.
Temperatures: 47 to 53 deg. F. 24 to 29 deg. F. 48 to 54 deg. F.
Mid Slope Winds: W Variable SW
Wind Speed: 10 to 15 mph with gusts to 35 mph. Light winds Generally light winds. Gusts up to 25 mph in the afternoon.
Expected snowfall: 0 0 0
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy skies. Clear skies. Sunny skies, becoming partly cloudy.
Temperatures: 39 to 47 deg. F. 25 to 30 deg. F. 42 to 48 deg. F.
Ridge Top Winds: W Variable SW
Wind Speed: 20 to 30 mph with gusts to 50 mph. Light winds 10 to 15 mph with gusts to 25 mph.
Expected snowfall: 0 0 0
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