THIS AVALANCHE ADVISORY EXPIRED ON March 26, 2017 @ 6:52 am
Avalanche Advisory published on March 25, 2017 @ 6:52 am
Issued by Steve Reynaud - Tahoe National Forest

Moderate avalanche danger will exist in near treeline and above treeline terrain due to wind slab avalanche problems.  Loose wet avalanches could develop today at all elevations especially if we receive more solar radiation than forecasted.  Human triggered avalanches are possible.  Evaluate snow and terrain carefully, identify features of concern.

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: Wind Slab
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Winds slabs will be possible on NW-N-NE-E-SE aspects in near treeline and above treeline terrain on slopes steeper than 35 degrees.  Active wind loading should diminish this morning as winds decrease, but existing wind slabs could still be reactive.  Look for blowing snow, cornice formation, wind pillows, snow surface scouring, and any clues as to current or previous wind loading.  Avoid steep wind loaded slopes and areas below cornices.

Avalanche Problem 2: Loose Wet
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Loose wet avalanches could develop on E-SE-S-SW-W aspects at all elevations as well as on NW-N-NE aspects below treeline.  The possibility exists for periods of more sunshine today than forecasted.  If rapid warming occurs due to solar radiation, then loose wet avalanche activity could become more widespread.  Small roller balls, wet surface snow, and long periods of full sun, could indicate that larger loose wet avalanches are possible.  Terrain traps, like gullies, can increase the consequences of even a small loose wet avalanche.

recent observations

Observations were made yesterday on Incline Lake Peak (Mt. Rose area).  The storm was just beginning in the mid morning hours with a couple inches of new snow.  Winds were strong out of the SW with small wind slabs forming along the summit ridge.  These wind slabs were not reactive at 12pm and were 3-5'' deep.  Storm intensity increased into the afternoon hours.

Weather and CURRENT CONDITIONS
weather summary

The main storm has dropped south out of our region.  Snowfall amounts of 4 to 10'' were seen throughout the forecast area above 7000'.  Convective snow showers are possible this morning that could produce up to a couple inches of snow where they develop.  The next storm is set for late Sunday night into Monday.  This storm is trending dryer and less impressive than the storm we just experienced.  Forecaster confidence remains low after Tuesday.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 24 to 29 deg. F.
Max. temperature in the last 24 hours: 34 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 20 to 50 mph
Maximum wind gust in the last 24 hours: 79 mph
New snowfall in the last 24 hours: 4 to 10 inches
Total snow depth: 126 to 177 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Saturday Saturday Night Sunday
Weather: Mostly cloudy. Scattered snow showers in the morning. Mostly cloudy. Mostly cloudy. Slight chance of snow in the morning then chance of snow in the afternoon.
Temperatures: 37 to 43 deg. F. 22 to 30 deg. F. 40 to 46 deg. F.
Wind Direction: SW SW
Wind Speed: Gusts up to 25mph in the morning. Light winds Light winds becoming 15 to 20mph with gusts to 40mph in the afternoon.
Expected snowfall: Trace to 1 in. 0 in. Up to 1 in.
For 8000 ft. to 9000 ft.
Saturday Saturday Night Sunday
Weather: Mostly cloudy. Scattered snow showers in the morning. Partly cloudy then becoming mostly cloudy. Mostly cloudy. Slight chance of snow in the morning then chance of snow in the afternoon.
Temperatures: 32 to 38 deg. F. 23 to 28 deg. F. 37 to 43 deg. F.
Wind Direction: SW SW SW
Wind Speed: 10 to 15mph. Gusts to 45mph decreasing to 25mph in the afternoon. 10 to 15mph in the evening then becoming light. Gusts up to 25mph. 20 to 30mph. Gusts to 45mph increasing to 60mph in the afternoon.
Expected snowfall: Up to 1 in. 0 in. 1 to 2 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