THIS AVALANCHE ADVISORY EXPIRED ON April 12, 2016 @ 6:43 am
Avalanche Advisory published on April 11, 2016 @ 6:43 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger continues for all elevations and aspects on slopes 35 degrees and steeper due to ongoing loose wet avalanche problems. Evaluate snow and terrain carefully. Identify and avoid steep terrain where unsupportable deep 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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    Certain
    Very Likely
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    Possible
    Unlikely
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    Historic
    Very Large
    Large
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Loose wet avalanche activity became more widespread yesterday. Little to no snow surface refreeze is expected to have occurred last night with cloud cover and above freezing air temperatures. Some degree of sunshine and air temperatures in the 40s today will keep loose wet instability ongoing on all aspects at all elevations. The vast majority of today's instability is expected to take the form of loose wet avalanches, however isolated wet slab and glide avalanches are not impossible.

Widespread areas of deep wet snow currently exist this morning and will continue to exist throughout the day today. Evaluate areas of wet snow for supportability. If in doubt, step off of equipment and observed the depth of body weight boot penetration into wet snow. Anything deeper than 8 to 10 inches is problematic. Avoid travel on or below slopes 35 degrees and steeper when unsupportable deep wet snow conditions are present.

recent observations

Observations made yesterday on Tamarack Peak (Mount Rose area) revealed storm snow amounts ranged from 2 inches at 8,600' to 6 inches at 9,700'. New snow was evenly distributed on all N-NE-E-SE aspects traveled, indicating light wind during deposition. Storm snow was decently, but not particularly well bonded to wet snow at the old/new snow interface. Recent high elevation rain had created wet snow in the top 2 feet of the snowpack on N aspects at 9,700'. At slightly lower elevations, up to 3 feet of wet snow existed on N aspects. Testpit data collected on a N aspect at 9,700' revealed no signs of slab instability associated with the recent new snow. Loose wet conditions were prominent below 9,000'. Skier triggered roller balls and pinwheels occurred in terrain steeper than 35 degrees at 8,800' and below at 10:30 am. Additional reports of skier triggered loose wet avalanche activity during the afternoon hours were received from this area.

Weather and CURRENT CONDITIONS
weather summary

The weather system that brought rain and snow to the forecast area over the past couple of days has departed the region. Residual moisture remains in place. Cloud cover thinning or partial clearing is expected today. The associated heating will contribute to convective showers occurring over the forecast area mainly during the mid and late afternoon hours. Snow level is expected in the 8,500' to 9,500' range today. Isolated thunderstorms are possible this afternoon. Maximum daytime air temperatures are expected in the low to upper 40s today for areas above 7,000'. Light winds are expected to continue through tonight. A drying trend and moderate speed SW winds are forecast for tomorrow.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 33 to 37 deg. F.
Max. temperature in the last 24 hours: 39 to 43 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 3 mph
Maximum wind gust in the last 24 hours: 20 mph
New snowfall in the last 24 hours: Rain 0.1 to 0.4 inches | Snow 0 to 1 inches
Total snow depth: 65 to 104 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Monday Monday Night Tuesday
Weather: Mostly cloudy skies with scattered rain showers. A slight chance of thunderstorms in the afternoon. Mostly cloudy skies, becoming partly cloudy. Scattered rain showers with a slight chance of thunderstorms in the evening. Partly cloudy skies, becoming mostly cloudy.
Temperatures: 43 to 50 deg. F. 27 to 34 deg. F. 44 to 51 deg. F.
Wind Direction: SW W SW
Wind Speed: Light winds increasing to 10 to 15 mph in the afternoon. 10 to 15 mph in the evening, becoming light. 15 to 20 mph. Gusts up to 30 mph in the afternoon.
Expected snowfall: 0 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Mostly cloudy skies with scattered rain and snow showers. Snow level 8,500' to 9,500'. A slight chance of thunderstorms in the afternoon. Mostly cloudy skies, becoming partly cloudy. Scattered rain showers with a slight chance of thunderstorms in the evening. Partly cloudy skies, becoming mostly cloudy.
Temperatures: 39 to 46 deg. F. 27 to 34 deg. F. 40 to 47 deg. F.
Wind Direction: SW W SW
Wind Speed: Light winds, increasing to 10 to 15 mph in the afternoon. 10 to 15 mph in the evening, becoming light. 10 to 15 mph with gusts to 25 mph, increasing to 20 to 25 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.

For a recorded version of the Avalanche Advisory call (530) 587-3558 x258