"Endless Winter Snow"

Snow Alert - Jackson Hole Wy, Snowbird Ut, Vail- Co, The Cascades Washington & Oregon

Happy Holidays from Endless Winter Snow . May all your runs be Freshie White

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AVALANCHE FORECASTS

* OLYMPICS- Wednesday to Thursday morning: Increasing CONSIDERABLE danger above 5000 feet and MODERATE below. Thursday afternoon and night: Danger decreasing and becoming CONSIDERABLE above 6000 and MODERATE below.

* WASHINGTON CASCADES NEAR AND WEST OF THE CREST INCLUDING THE CASCADE PASSES- Wednesday to Thursday morning: Increasing CONSIDERABLE danger above 4000 feet and MODERATE below. Thursday afternoon and night: Danger decreasing and becoming CONSIDERABLE above 5000 and MODERATE below.

* EAST SLOPES WASHINGTON CASCADES- Wednesday to Thursday morning: Increasing CONSIDERABLE danger above 5000 feet and MODERATE below. Thursday afternoon and night: Danger decreasing and becoming CONSIDERABLE above 6000 and MODERATE below.

* MT HOOD AREA- Wednesday to Thursday morning: Increasing CONSIDERABLE danger above 5000 feet and MODERATE below. Thursday afternoon and night: Danger decreasing and becoming CONSIDERABLE above 6000 and MODERATE below. SNOWPACK ANALYSIS Only light amounts of new snow accumulated Monday and Tuesday. This should have allowed the snow layers to partly consolidate and slightly stabilize. No avalanches were reported the past 2 days.

The last main weather event was last weekend when moderate amounts of snow were seen along with some very strong northeast to southeast crest level winds. This should have transported snow to lee slopes and created some local slab layers. Another strong easterly winds event was seen about the previous weekend.

The main weather factor lately has been the cold weather. Reports such as on the FOAC web site indicate that this has led to a generally weak snowpack with faceted layers, with some local firmer wind layers sandwiched in as well. Widespread surface hoar frost was reported by the Crystal Mountain ski patrol on Tuesday. This snowpack may cause significant avalanche conditions when loaded by significant snowfall at more normal temperatures this weekend.

Bridger-Teton National Forest Avalanche Center
An Avalanche Warning has been issued by the Bridger-Teton National Forest Avalanche Center from 11pm tonight through 11pm Thursday night: Large destructive avalanches are certain in the backcountry and could impact roadways. The primary hazard will be to people who venture into the backcountry to recreate, however bank slides and roof slides are also a concern in residential areas.

The general avalanche hazard is expected to be High on Christmas day and potentially Extreme in the Southwest Trails/Greys River area depending on the snowfall and wind received there. Large, dangerous slabs three to six feet in depth are expected to release naturally or easily to human triggers above 8000’. The likelihood and size of these natural or human triggered events will increase as snowfall and strong winds continue throughout the day. Travel in avalanche terrain is not recommended

Sierra Avalanche Center
MODERATE with pockets of CONSIDERABLE on NW-N-NE-E-SE slopes steeper than 35 degrees. Below treeline the avalanche danger will increase to MODERATE on open slopes steeper than 35 degrees. The avalanche danger will continue to rise overnight.

www.sierraavalanchecenter.org/

The Sierra Avalanche Center is a 501(3)(c) not-for-profit organization working in partnership with the Tahoe National Forest to provide avalanche advisories. The vast majority of our funding comes from private donations and our fund raising events. Please consider making a tax deductible donation to the Sierra Avalanche Center using the PAYPAL link below

Paypal Donations to Sierra Avalanche Center

Swiss Alps:
Avalanche danger forecast for Christmas day

Entire region of the Swiss Alps:
Moderate avalanche danger (Level 2)
In the eastern part of the northern flank of the Alps not including the Prealps, as well as in Grisons, the avalanche prone locations are to be found on steep slopes in all aspects above approximately 2000 m. In the remaining regions, the avalanche prone locations are found primarily on wind loaded slopes above approximately 2200 m. In southern Valais, the avalanche prone locations are in all aspects, elsewhere primarily on southwest to north to southeast facing slopes and in areas adjacent to ridge lines in all aspects. In very isolated cases, avalanches can be triggered even by a single backcountry skier or freerider. Some of the avalanche prone locations lie inside the old snowpack, making them nearly impossible to recognize. They become more frequent with rising altitude. Freshly formed snowdrift should be avoided whenever possible. Cautious route selection and spacing to relieve loads are important.

In all regions on south facing slopes below about 2500 m, elsewhere below about 2200 m, full depth snowslides continue to be expected. Glide cracks are indicators of the danger spots.

A word about Avalanches:
The following three factors MUST be present for an avalanche to occur:

1) Terrain: The slope must be steeper than about 30 degrees and most often steeper than about 35 degrees. Slopes less than about 30 degrees are not steep enough to avalanche.

2) Snowpack: The snow must be unstable. Mountain snowpacks are a series of layers stacked on top of one another. Some of the layers are hard and strong, some of them are soft and weak. The snowpack is unstable when a harder stronger layer sets on top of a softer weaker layer and the soft weak layer can barely support the hard strong layer above it.

3) Trigger: A trigger provides the stress that causes the weak layer to collapse and the snowpack to avalanche. A triggger could be additional weight from more snow or it could be you.

Spend some time taking in the public service RISK ANALYSIS information available at: www.fsavalanche.org/

Kirkwood - Ca
Another 6-8" of snow so far today, another 12-18" expected by Christmas Day morning. We will update this web report no later than 6am Christmas Day, which has all the signs of pure epic conditions. Today, again, unreal. We are now hovering around 10' of new snow in 10 days, continues to be lighter, drier than any previous December we can remember, all lifts are scheduled, a few delays as Ski Patrol does their work, which starts at the first sign of light. We have 100% of the mountain now open www.kirkwood.com

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