Northern Rockies/Alberta Avalanche at Silver

[karlo]

CAIC will publish
The initial item is here: https://avalanche.state.co.us/caic/acc/acc_report.php?acc_id=731&accfm=rep

Thanks.

So, this avalanche at Silver Mountain Resort was a skier triggered large avalanche,

Avalanche Type: SS Trigger: AS - Skier Trigger (subcode): u - An unintentional release Size - Relative to Path: R3 Size - Destructive Force: D3 Sliding Surface: O - Within Old Snow

Site Slope Aspect: E Site Elevation: 6200 ft Slope Angle: 35 ° Slope Characteristic: --

Size details, “The avalanche released about 90 feet below a corniced ridgeline on a buried layer of surface hoar. The crown face was about 2 to 3 feet deep and 300 feet wide. The avalanche ran over 900 feet downhill and about 450 feet vertically.”

Size classifications,https://www.slf.ch/en/avalanche-bul...t-the-avalanche-bulletin/avalanche-sizes.html

I don’t recall the source, but I recall reading that there were three unintentional avalanches there that day. I think that means the avy hazard was at least Level 3, maybe Level 4 on account of there having been three avalanches. Reference here,

Avalanche Safety - Avalanche Risk Scale

Tips and Advice for Avalanche Safety - Avalanche Risk Scale

www.j2ski.com

From the same page, “Every modern ski resort will issue notices (bulletins) indicating the level of Avalanche Risk for each day.”

This was apparently in a more remote area of the resort, Wardner Peak.

2 Killed, 5 Injured In Avalanche At Idaho Ski Resort

The avalanche occurred Tuesday morning at the Silver Mountain Resort in the Idaho Panhandle. The slide follows wet, heavy snowfall in recent days that brought high avalanche danger.

www.npr.org

I wonder what Avalanche Risk level Silver published for Wardner Peak area.

 

[New2]

Update from the Spokesman-Review: Skiers triggered deadly Silver Mountain avalanche despite best efforts of ski patrol, preliminary investigation says

I wonder what Avalanche Risk level Silver published for Wardner Peak area.

I think the Idaho Panhandle Avalanche Center handles publishing risk level for Silver, Schweitzer, Lookout, and Turner, rather than the individual resorts/ski patrols. The whole region was flagged Level 4 High Risk - Red.

 

[Jwrags]

Not sure where to post this but found it interesting. Mt. Bachelor just finished a huge snow cycle and when they get the NW Express lift open they are implementing the following

“

• When Northwest opens, mandatory buddy riding WILL be required in the West Bowls. What this means is Ski Patrol may be checking buddies at entry points to West Bowls. If you exit a run and lift without your buddy we will be checking in on what happened, and you may / may not be able to load the lift until buddies have been reconnected. Be smart, be safe, be cool, stay stoked.“

I have never heard of this before but it seems like a good idea.

 

[karlo]

Update from the Spokesman-Review: Skiers triggered deadly Silver Mountain avalanche despite best efforts of ski patrol, preliminary investigation says
I think the Idaho Panhandle Avalanche Center handles publishing risk level for Silver, Schweitzer, Lookout, and Turner, rather than the individual resorts/ski patrols. The whole region was flagged Level 4 High Risk - Red.

@Unpiste pointed that out too, that risk assessment for the region does not apply to a resort. It’s still interesting to see to what degree the Avy Center’s assessment applied in this case. They do have a reported observation from near Wardner Peak Traverse,
https://www.idahopanhandleavalanche...extended-column-testing-rutschblock-site-1222
Not sure if the observation was on 12/22 and reported on 12/28, or if it was on 12/28. I wonder if the surface hoar observed is the same layer noted in the Spokesman Review article. For those unfamiliar with what surface hoar is, check this out,

http://cbavalanchecenter.org/what-is-surface-hoar/

The photo tells it all. Though the crystals compact and change, if there, it’s still layers and layers of newer snow on stilts, on a “persistent weak layer”.

There were three advisories that morning. The relevant one?, for Silver Valley, is here,
https://www.idahopanhandleavalanche...n/7/2020-01-07-054957-avalanche-advisory#null
The presence of persistent weak layers is noted. And, if resort mitigation and skier traffic is dealing with the persistent weak layers, then it’s a different ball of wax. If not, then the regional assessment might be very applicable. I would still be interested in knowing whether or not, as the j2ski.com page says “modern” resorts do, Silver Mountain Resort published a risk assessment for Wardner Peak. If so, from what observations, collected over the season, did they make that assessment.

SR article: “ in addition to the specific mitigation techniques used and decisions made, will be released by Silver Mountain some time in the “next couple weeks,” said Silver Mountain spokesman Gus Colburn.”

Decisions are based on assessments.

The article speaks of the crown location and that it was skier triggered. More details and photos are in the
CAIC report found here,
https://avalanche.state.co.us/caic/acc/acc_report.php?acc_id=731&accfm=rep




Looking at the trail map, the photo, and with my understanding of where the skiers were (on 16 to 1, coming off Wardner Peak Traverse), am I correct that the skiers were well below the crown of the slide? If so, though skier triggered, it didn’t take much to trigger. ! I.e., it’s not like anyone skied where the crown is. And, per the SR article, the weak layer was deep, so also old. Could it really be that weak? Guess so.

 

[Tricia]

Survivor of Silver Mountain Avalanche tells his story

How I Survived Two Consecutive Avalanches

Buried for more than an hour and resigned to the worst, a skier recounts his dramatic rescue. It's a tale especially important for those headed into the backcountry

mountainjournal.org

I believe Ken Scott that shared his story is Pugski member @Ken Scott

 

[Kneale Brownson]

Anyone going out there now, especially with fresh snow on top of old, hard, sun-baked snow, is not thinking.

 

[Tricia]

Anyone going out there now, especially with fresh snow on top of old, hard, sun-baked snow, is not thinking.

While I agree with you that the snow pack is pretty unstable right now, I'm not sure that your post is in context with the story I linked.

 

[Kneale Brownson]

Last line in the report: EDITOR'S NOTE: While ski resorts in the US are now closed, many people are still headed into the backcountry. It is vitally important for all recreationists to be prepared for avalanche conditions. For more information, click here.

That's what prompted my reply.

 

[Tricia]

Last line in the report: EDITOR'S NOTE: While ski resorts in the US are now closed, many people are still headed into the backcountry. It is vitally important for all recreationists to be prepared for avalanche conditions. For more information, click here.

That's what prompted my reply.

Ah, I get the context now.

 

[raisingarizona]

Anyone going out there now, especially with fresh snow on top of old, hard, sun-baked snow, is not thinking.

Those conditions can be pretty simple to mitigate risk and travel through honestly, at least for the experienced. Deep, mid winter long lasting instabilities are a lot more complicated and scary imho.

 

[New2]

The Spokesman-Review today had a big front-page feature recapping and updating:

• Those who survived the deadly Silver Mountain avalanche say it offers painful lessons
• Loved ones remember how 3 killed in Silver Mountain avalanche sought adventure, spread goodwill

@Tricia I'm not sure how this thread ended up with a "Colorado" tag, but Northwest and/or Northern Rockies would be more appropriate.

 

[dbostedo]

@Tricia I'm not sure how this thread ended up with a "Colorado" tag, but Northwest and/or Northern Rockies would be more appropriate.

I fixed it. And don't call me Shir... er... Tricia.

 

[Mike King]

The Spokesman-Review today had a big front-page feature recapping and updating:

• Those who survived the deadly Silver Mountain avalanche say it offers painful lessons
• Loved ones remember how 3 killed in Silver Mountain avalanche sought adventure, spread goodwill

@Tricia I'm not sure how this thread ended up with a "Colorado" tag, but Northwest and/or Northern Rockies would be more appropriate.

Pretty frightening account...

 

[Tricia]

The Spokesman-Review today had a big front-page feature recapping and updating:

• Those who survived the deadly Silver Mountain avalanche say it offers painful lessons
• Loved ones remember how 3 killed in Silver Mountain avalanche sought adventure, spread goodwill

@Tricia I'm not sure how this thread ended up with a "Colorado" tag, but Northwest and/or Northern Rockies would be more appropriate.

Whenever I read those personal recollections of people on the scene or directly involved it sends chills up my spine.

 

[Philpug]

We are talking about this right now on SkiTalk w/Dan Egan on Facebook.

 

[Tricia]

For those interested, here is the link the episode of SkiTalk with Dan Egan.
Ken recall of his burial at Silver is compelling

 

[DanoT]

Excellent show, especially the interview with one of the Silver Mtn. avalanche survivors.

 

[James]

Another good ski talk.Will have to check out Henry’s Avalanche site.

Dan mentioned a recent deadly slide on the Lognan to Val Claret near Tignes. Don’t know the Lognan, but many years ago on a high school trip we stayed in Val Claret. There was a fantastic run down to the area where we were staying. This was all off piste. We didn’t know a thing about avalanches, other than they happened. No equipment.
In a week we probably did this run four times. Usually there was untracked. It involved a very long traverse over from Tignes. One time I set off a small slab like 10 x 30 ft maybe 6-8 in thick. It was i ncredibly disorientating, and that wasn’t much of a drop. But when the ground goes out, your brain just kind of misfires. I suppose one could train themselves to overcome the initial disorientation more quickly.

We were lucky in that nothing more ever happened. We didn’t push things that much. Thankfully, ski movies barely existed then to goad us on as you needed a theater. It was Patrick Vallencant on the extreme steeps, not pow slaying.

 

[GRIFFM3]

On a lighter note Sun Valley is now up to 26" of snow in the last 72 hours and another 20" expected...this is madness!

 

[Tricia]

On a lighter note Sun Valley is now up to 26" of snow in the last 72 hours and another 20" expected...this is madness!

Looks like you're in the path of the same storm we're getting.
We have gotten anywhere from 4' to 6' depending on where you're located in our region.
Mt Rose reported 51"
Squaw 59"
Mammoth reported 76"