THIS AVALANCHE ADVISORY EXPIRED ON March 30, 2016 @ 6:59 am
Avalanche Advisory published on March 29, 2016 @ 6:59 am
Issued by Steve Reynaud - Tahoe National Forest

Moderate avalanche danger could exist on NE-E-SE-S-SW-W aspects near and above treeline due to newly forming wind slabs.  These wind slabs should be limited mainly north of Hwy 50 where we received more snow in the last 24 hours.  Loose wet avalanches are unlikely today but could occur if we receive large periods of sun and less cloud cover than forecasted.  Adjust terrain choices and route selection according to localized conditions.

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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We received some additional snow overnight with increased and changing winds.  Wind slab avalanches could be possible today on NE-E-SE-S-SW-W aspects near and above treeline.  Winds have been variable depending on location, anywhere from the NW-N-NE with speeds ranging from 20 to 30mph with gusts up to 50mph.  Over the last 24 hours, more snow accumulation has occurred north of Hwy. 50 and on the Eastern side of the forecast area.  These areas with more available snow for wind transport and winds strong enough to move snow will be of most concern.   

Be aware of highly localized avalanche conditions today and avoid potentially unstable wind slabs where they have formed. Use clues such as blowing snow, recent avalanche activity, cornice formations, wind pillows, snow surface scouring, and human triggered snow surface cracking to help identify areas to avoid.

Avalanche Problem 2: Loose Wet
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There is some uncertainty as to how much sun we will see today.  If sun breaks do develop and we receive large amounts of solar radiation, loose wet avalanches could occur on E-SE-S-SW-W aspects.

Look for small surface instabilities like roller balls, pinwheels, or point releases. Once the surface snow becomes wet it's time to change aspects and move off and away from slopes that are 35 degrees or steeper. Terrain traps like gullies, creeks, and cliffs can greatly increase the risk of any size loose wet avalanches.

 

recent observations

Observations yesterday from Tamarack Peak (Mt. Rose area) showed up to 8'' of new storm snow by early afternoon.  Very little evidence of any wind transport was seen in this area with little to no wind slab development observed.  Loose dry sloughs were common in steeper terrain >40 degrees which involved the top few inches of surface snow.  Snowfall was consistent throughout the day and continued on departure.

Weather and CURRENT CONDITIONS
weather summary

An upper low over Eastern Nevada will move little today and bring the chance for snow showers and plenty of clouds throughout today.  Temperatures will remain below normal in the mid 20's to mid 30's above 7000' with North winds 15 to 25mph gusting to 40mph.  Chance for additional snow showers this afternoon with light accumulations of up to 1''.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 10 to 19 deg. F.
Max. temperature in the last 24 hours: 21 to 29 deg. F.
Average wind direction during the last 24 hours: NE to NW
Average wind speed during the last 24 hours: 25 to 35 mph
Maximum wind gust in the last 24 hours: 57 mph
New snowfall in the last 24 hours: Trace to 4 inches
Total snow depth: 81 to 122 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy. Isolated snow showers in the morning then scattered snow showers in the afternoon. Mostly cloudy. Scattered snow showers in the evening then isolated showers after midnight. Mostly cloudy. Slight chance of snow.
Temperatures: 30 to 35 deg. F. 14 to 21 deg. F. 35 to 40 deg. F.
Wind Direction: NE to NW NW to NE NE
Wind Speed: NE 10 to 15mph with gusts to 25mph becoming NW 10 to 20mph with gusts to 30mph in the afternoon. NW 10 to 15mph with gusts to 25mph becoming NE 10 to 20mph after midnight. 10 to 20mph.
Expected snowfall: Up to 1 in. Up to 1 in. 0 in.
For 8000 ft. to 9000 ft.
Tuesday Tuesday Night Wednesday
Weather: Mostly cloudy. Isolated showers in the morning then scattered showers in the afternoon. Mostly cloudy. Scattered showers in the evening then isolated showers after midnight. Mostly cloudy. Slight chance of showers.
Temperatures: 26 to 32 deg. F. 13 to 20 deg. F. 27 to 34 deg. F.
Wind Direction: N N NE
Wind Speed: 15 to 25mph with gusts to 40mph. 15 to 25mph with gusts to 35mph. 15 to 25mph with gusts to 40mph.
Expected snowfall: Up to 1 in. Up to 1 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