THIS AVALANCHE ADVISORY EXPIRED ON March 24, 2015 @ 6:57 am
Avalanche Advisory published on March 23, 2015 @ 6:57 am
Issued by Andy Anderson - Tahoe National Forest

The avalanche danger will remain LOW in most places today since snow accumulations remained light. Some pockets of MODERATE avalanche danger may exist on wind loaded NW-N-NE-E-SE aspects 35 degrees and steeper in near and above treeline terrain in areas that received the most new snow. Small human triggered wind slabs may be possible in these areas.

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.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    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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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
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    Historic
    Very Large
    Large
    Small

Small human triggered wind slabs will be possible today on some wind loaded and cross loaded NW-N-NE-E-SE aspects in near and above treeline terrain. Since snow fall amounts remained relatively small, most of the wind slabs that have formed should also remain relatively small and not extend very far down slope. In some of the more heavily wind loaded areas where the most new snow fell wind slabs around a foot in depth may exist. Wind loaded slopes near ridge lines along the Sierra Crest north of Hwy 50 represent the best places to find the largest winds slabs. Even though most wind slab activity expect today should not involve enough snow to  bury a person, small avalanches can still be problematic in the right terrain. Areas like wind loaded slopes above cliffs, gullies, and other terrain traps can magnify the consequences of any size avalanche.

recent observations

Yesterday observations on Chickadee Ridge showed a mix of frozen surfaces on northerly aspects and a few inches of soft wet corn snow on E-SE-S-SW aspects. Regardless of the surface conditions, the underlying snowpack remained strong and well bonded. Data from this area yesterday as well as many other areas around the forecast area during the last week indicates that the current snow pack should be able to handle new loading well.

Weather and CURRENT CONDITIONS
weather summary

As the cold front moved across the region last night, snow levels dropped from between 7000 and 7500 ft. to around 6000 ft. this morning. Remote sensors report between 2 and 4 inches of new snow in areas above 7000 ft. Areas along the Sierra Crest north of Hwy 50 received the most accumulation. Snow showers should continue this morning before they start to taper off this afternoon as the system moves away from the area. The forecast calls for up to one more inch of new snow today. Southwest winds remained strong last night and should continue this morning. As the snow showers taper off this afternoon, the winds should also begin to decrease. The cooler temperatures that accompanied the cold front should persist through tonight before another warming trend begins tomorrow. Above 7000 ft. the forecast calls for daytime highs in the 30's today and mid 40's for tomorrow.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 24 to 30 deg. F.
Max. temperature in the last 24 hours: 35 to 45 deg. F.
Average wind direction during the last 24 hours: Southwest
Average wind speed during the last 24 hours: 35 to 40 mph
Maximum wind gust in the last 24 hours: 72 mph
New snowfall in the last 24 hours: 2 to 4 inches
Total snow depth: 18 to 43 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Monday Monday Night Tuesday
Weather: Cloudy with snow showers in the morning. Snow showers becoming isolated in the afternoon Mostly cloudy with a slight chance of snow showers Mostly cloudy with a slight chance of snow showers
Temperatures: 38 to 44 deg. F. 20 to 27 deg. F. 42 to 48 deg. F.
Wind Direction: Southwest Southwest West
Wind Speed: 25 to 35 mph with gusts to 55 mph decreasing to 45 mph in the afternoon 20 to 25 mph with gusts to 35 mph decreasing to 10 to 15 mph with gusts to 25 mph after midnight 15 to 20 mph with gusts to 30 mph
Expected snowfall: up to 1 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Cloudy with snow showers in the morning. Snow showers becoming isolated in the afternoon Mostly cloudy with a slight chance of snow showers Mostly cloudy with a slight chance of snow showers
Temperatures: 33 to 39 deg. F. 22 to 28 deg. F. 38 to 44 deg. F.
Wind Direction: Southwest Southwest West
Wind Speed: 35 to 45 mph with gusts to 65 mph 20 to 30 mph with gusts to 45 mph decreasing to 35 mph after midnight 20 to 30 mph with gusts to 45 mph decreasing to 35 mph in the afternoon
Expected snowfall: up to 1 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.