23-24

High Winds and Warm Temps on Blackmore

Date
Activity
Skiing

Warm temps made for wet snow and gloping on the tour up toward Blackmore. At about 8400' the conditions changed with winds keeping the snow surface dry and cold. Upon entering the basin we saw the skier triggered slide reported on 01/19 as well as another slide off the west side of the peak, both D2. The crown of the westward slide looked to be around 4'. Like the one reported the other day, it ran almost to the skin track. Winds were high in the basin and on the ridge tops, transporting snow into moderately stiff slabs. At around 12PM the snow surface up high was getting wet and by the time we reached the parking lot it felt like your typical sunny day in April. 

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Sam Lowe

Rain in the Bridgers

Date
Activity
Skiing

Saturday morning above freezing with wet, sticky snow and then it started to rain. Rained perhaps 1 hour from at least 7200 feet back to the parking area. Should have waxed for May!

Region
Bridger Range
Location (from list)
Brackett Creek

Blackmore recent slides

Date
Activity
Skiing

Snow has weak layers from recent storm and old facets. Dug a quick pit and found what’s been going on all season. 

Two distinct slides-

1. Off the top on the face of Blackmore- Talked to the guy that set this slide off, it was triggered while he was skiing down yesterday morning from the summit. Ran all the way down to almost the skin track. 

2. A much bigger one on lookers left of Blackmore peak, naturally occurring as there were no tracks near it.  Looked like a bigger crown. Talking to the guy who triggered the slide yesterday he stated this one wasn’t there yesterday. 

Lots of wind when I was up there this morning skiing the shoulder, could see loading happening throughout the range. Sun came out and warmed everything up. 46 degrees at Hyalite parking lot when I got back to my car just before 1:00pm. Saw roller balls driving back down on the road on the steep hillsides. 

Thanks for all you do! 

 

Region
Northern Gallatin
Location (from list)
Mt Blackmore
Observer Name
Nick English

Natural avalanche mt Blackmore

Date
Activity
Skiing

While up there investigating yesterday’s avalanche i noticed a new debris coming out of the lookers left chute on Southeast face a blackmore. got closer to the ridge and noticed this. happened last night or this morning.  wind was definitely pumping a change. Directions loading this aspect. debris ran out of side of this picture.  5 feet deep 50 to 100 ft wide and ran roughly 800 feet. 

Region
Northern Gallatin
Location (from list)
Mt Blackmore

Skier triggered avalanche mt blackmore

Date
Activity
Skiing

Observed the avalanche breaking pretty far down the ridge, but I had a feeling it broke a little bigger judging by how fast the powder cloud was the moving. Went back up there today and saw that it had in fact, broke quite a bit bigger than the 8 inches and 50 feet I initially reported. Photo attached.

Region
Northern Gallatin
Location (from list)
Mt Blackmore

GNFAC Avalanche Forecast for Sat Jan 20, 2024

Snowpack and Avalanche Discussion

<p><span><span><span><span><span><span>Large, dangerous human triggered avalanches are likely today. Don’t let the expiration of yesterday’s avalanche warning for Cooke City lull you into any sort of complacency, conditions remain quite dangerous. Avalanches can be triggered from far away and from the bottom of slopes. Yesterday was quieter, but look to all the remotely triggered avalanches on Thursday for examples of what we’re concerned about (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=74rb5HCvbsE"><span><span><span><strong>… City video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30037"><span><span><span><strong><span… photos</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30046"><span><span><span><strong><span… Fork photos</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Recent avalanches are the best clue that you can trigger more avalanches (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=LzkWoa4viY0&amp;t=1s"><span><span><span… Park video</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). These slides are being triggered from hundreds of feet away and breaking 1-2 ft deep on weak layers of surface hoar and facets. With these types of weak layers, stability does not improve quickly. Avalanches can be triggered days and even weeks after the last loading event. Winds have been pretty moderate, but particularly watch for slopes where drifting snow has continued to load the weak layers. Continue to avoid slopes steeper than 30 degrees and be skeptical crossing beneath them as well.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The avalanche danger is CONSIDERABLE in the mountains around Cooke City, West Yellowstone and Island Park.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Triggering dangerous avalanches, perhaps from a distance, remains very possible. The danger rating came down a step only because these slides are just a little bit less likely than yesterday. Thursday’s remarkably wide avalanche on Buck Ridge (</span></span></span></span></span></span><a href="https://www.youtube.com/watch/IoM5zbOF5E4"><span><span><span><strong><s…;) and slides triggered from 150 ft away in </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30026"><span><span><span><span><span><…; are good examples of the dangerous and surprising avalanches that are possible today.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Wind loaded and wind effected slopes are the most concerning. A skier triggered an avalanche on a windloaded slope just below the ridgeline on the E face of Mt. Blackmore yesterday (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30064"><span><span><span><strong><span…;). It broke around 8” deep, 50 ft wide and ran almost all the way to the typical skin track. Skiers near Big Sky and in the Bridger Range noted cracking and collapsing, indications that the weak layers in the snowpack remain ready to avalanche (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/30059"><span><span><span><span><span><… Sky observation</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Continuing to avoid riding on or under slopes steeper than 30 degrees is a reasonable tactic for a low stress day. If you are going to travel in avalanche terrain, be highly alert for signs of instability and doubly wary of any slope where the snow has been affected by the wind.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The avalanche danger is MODERATE near Bozeman and Big Sky.</span></span></span></span></span></span></p>

Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.

Skier triggered slide on Mt. Blackmore

Mt Blackmore
Northern Gallatin
Code
HS-ASu-R2-D2
Aspect
SE
Latitude
45.44440
Longitude
-111.00400
Notes

A skier triggered an avalanche on the SE face of Mt. Blackmore near the ridge on the morning of 1/19/24.

From text:  "Hard to with the visibility but it ran almost all the way to the skin track (~800 vertical). It definitely broke 8 inches deep and 50 ft wide, but it might've gotten a little wider and deeper."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
2
D size
2
Slab Thickness
8.0 inches
Vertical Fall
800ft
Slab Width
50.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skier triggered slide on Blackmore

Date
Activity
Skiing

A skier triggered an avalanche on the SE face of Mt. Blackmore near the ridge on the morning of 1/19/24.

From text:  "Hard to with the visibility but it ran almost all the way to the skin track (~800 vertical). It definitely broke 8 inches deep and 50 ft wide, but it might've gotten a little wider and deeper."

Region
Northern Gallatin
Location (from list)
Mt Blackmore

Cracking and Collapsing in Jones Creek

Date
Activity
Skiing

From text: "I'm back poking around on the ridge between Truman Gulch and Jones Creek today. The wind has moved enough snow to create some pockets of denser snow that will crack and whumph in places. It definitely feels a little upside down in places."

Region
Bridger Range
Location (from list)
BRIDGER RANGE
Observer Name
Pat Hinz