THIS AVALANCHE FORECAST EXPIRED ON March 28, 2018 @ 6:52 am
Avalanche Forecast published on March 27, 2018 @ 6:52 am
Issued by Steve Reynaud - Tahoe National Forest

MODERATE avalanche danger will exist today due to wind slab and loose wet avalanche problems.  Wind slabs will be possible in near and above treeline terrain.  Loose wet avalanches will become possible at all elevations as daytime warming occurs.  Heightened avalanche conditions exist on specific terrain features, identify areas 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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Strong to gale force NE winds will continue through this morning before decreasing in the afternoon.  Wind slabs will be possible on SE-S-SW-W-NW aspects in near and above treeline terrain.

Look for recent wind slab avalanche activity, blowing snow, new cornice formation, wind pillows, and snow surface scouring as to where wind slabs may exist.  Complex terrain and/or steep gully features may be cross loaded.  Identify and avoid steep wind loaded terrain.

Avalanche Problem 2: Loose Wet
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As rapid warming occurs today with sunny skies, loose wet avalanches will become possible on all aspects and elevations.  Many of the loose wet instabilities will be focused on E-SE-S-SW-W aspects.  As the NE winds decrease this afternoon along with increasing daytime temperatures, wet instabilities will also become possible on NW-N-NE aspects at all elevations.  Most wet instabilities will be in the form of roller balls and pinwheels.  Larger loose wet avalanches are possible with some of these being large enough to injure or bury a backcountry user-size D2.

Roller ball activity will be an indication that the slope has wet surface snow and is loosing strength.  Steep terrain with wet surface snow should be avoided. 

   

recent observations
Submit Observations

* On Hidden Peak (West Shore area) a small wind slab avalanche was intentionally skier triggered on a SE aspect in near treeline terrain.  NE winds were scouring snow surfaces and blowing snow in near treeline and above treeline terrain.  Dense wind slabs measured up to 16'' in depth.  No instabilities were found in below treeline terrain.

* Observations from Trimmer Peak (Luther Pass area) showed no instabilities on northerly aspects through the mid day.  NE winds remained light for most of the day with minor evidence of previous wind scouring at the higher elevations.

* Numerous crowns from deep slab avalanche activity occurring during the March 20 - 22 storm cycle exist on N-NE-E aspects both above and below treeline in the 7,000' to 10,000' elevation range. No reports of post storm deep slab avalanches have been received.  Check out the observation page for more details and photos. 

Weather and CURRENT CONDITIONS
weather summary

High pressure continues to build throughout the forecast region.  Strong to gale force NE winds have been occurring along the higher elevation ridges and peaks with wind speeds in the 40 to 60mph range and gusts up into the 80mph range.  These NE winds should moderate in speed this afternoon and slowly decrease into Wednesday.  Air temperatures will continue to warm throughout the week with daytime highs forecasted to be in the high 30's low 40's above 8000' for today.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 19 to 25 deg. F.
Max. temperature: 32 deg. F.
Average ridgetop wind direction: NE
Average ridgetop wind speed: 40 to 60 mph
Maximum ridgetop wind gust: 83 mph
New snowfall: 0 inches
Total snow depth: 85 to 115 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny Clear Sunny
Temperatures: 42 to 47 deg. F. 25 to 30 deg. F. 48 to 53 deg. F.
Mid Slope Winds: NE/E NE E
Wind Speed: 10 to 15mph with gusts to 25mph Up to 10mph Up to 10mph
Expected snowfall: 0 0 0
For 8000 ft. to 9000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny Clear Sunny
Temperatures: 37 to 43 deg. F. 25 to 30 deg. F. 43 to 49 deg. F.
Ridge Top Winds: NE NE NE
Wind Speed: 35 to 55mph with gusts to 75mph decreasing to 20 to 30mph with gusts to 40mph in the afternoon 15 to 25mph with gusts to 40mph 10 to 15mph with gusts to 30mph
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