THIS AVALANCHE FORECAST EXPIRED ON April 1, 2018 @ 6:59 am
Avalanche Forecast published on March 31, 2018 @ 6:59 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

The avalanche danger will increase to MODERATE as the day warms up. Loose wet avalanche problems will become possible. 

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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    Very Likely
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Warm temperatures last night coupled with overnight cloud cover should have prevented a good refreeze from occurring in many areas. While today's cloud cover and slightly cooler temperatures may not melt the snow as quickly as yesterday's sunny warmer weather, today's warming should still be enough to melt through the minimal to non-existent refreeze from last night. Loose wet avalanche activity will become possible again especially on sun-exposed E-SE-S-SW-W aspects. The cloud cover could also help spread the warmth to the more northerly aspects and some loose wet instability could exist on those slopes. Wet snow instabilities could include pinwheels, rollerballs, and loose wet avalanches. Some of the loose wet avalanches could involve enough snow to injure a person.

Wet sticky snow, boot-top-deep wet snow, active roller balls or pinwheels, and other loose wet avalanches can indicate increasing wet snow instability.  Once signs of wet snow exist, move to a colder more shaded aspect or lower angle slopes. Planning an early start and an early finish can help avoid loose wet avalanche issues. 

recent observations
Submit Observations

* A layer of soft wet melt-freeze snow resting on top of a supportable melt-freeze crust formed on sun-exposed aspects by 10:30-11:00 am yesterday on Chickadee Ridge by (Mt Rose backcountry), Stevens Peak (Carson Pass area), and Angora Peak (Echo Summit area).

* By noon yesterday, ski cuts on test slopes triggered pinwheels on Stevens Peak and on Chickadee Ridge.

* On the sun-exposed lower elevations of Angora (below 7000 ft), stepping into the wet snow resulted in post-holing to the ground at 8:30 in the morning. On Chickadee Ridge, boot-top to mid-shin deep wet snow existed on sun-exposed aspects by noon.  

* Several recent loose wet avalanches had occurred in the past 3 days on sun-exposed slopes in the Mt. Rose backcountry.

Weather and CURRENT CONDITIONS
weather summary

Cloud cover and southwest winds started increasing over the area yesterday afternoon and persisted through the night. This layer of thin high clouds should become more widespread today as a weak low-pressure system moves through the Pacific NW. Clouds should start to clear out tonight and the forecast calls for a sunny day tomorrow. The winds should also linger through tomorrow with periods of light wind and periods of moderate wind. Daytime highs should remain about 5 degrees cooler than yesterday for both today and tomorrow. 

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 38 to 42 deg. F.
Max. temperature: 50 to 56 deg. F.
Average ridgetop wind direction: Southwest
Average ridgetop wind speed: 10 to 20 mph
Maximum ridgetop wind gust: 33 mph
New snowfall: 0 inches
Total snow depth: 70 to 103 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Saturday Saturday Night Sunday
Weather: Partly cloudy becoming mostly cloudy Partly cloudy becoming clear Sunny
Temperatures: 52 to 57 deg. F. 28 to 33 deg. F. 53 to 58 deg. F.
Mid Slope Winds: Southwest Southwest Southwest
Wind Speed: Light in the morning increasing to 10 to 15 mph with gusts to 35 mph in the afternoon 10 to 15 mph with gusts to 35 mph in the evening becoming light overnight Light in the morning increasing to 10 to 15 mph with gusts to 30 mph in the afternoon
Expected snowfall: 0 0 0
For 8000 ft. to 9000 ft.
Saturday Saturday Night Sunday
Weather: Partly cloudy becoming mostly cloudy Partly cloudy becoming clear Sunny
Temperatures: 46 to 52 deg. F. 28 to 33 deg. F. 46 to 52 deg. F.
Ridge Top Winds: Southwest Southwest Southwest
Wind Speed: 15 to 25 mph with gusts to 40 mph 15 to 20 mph with gusts to 35 mph 15 to 25 mph with gusts to 40 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