Northern Gallatin

Skiers saw a recent natural avalanche on the west side of Mt. Blackmore. Photo: S. Lowe

From obs: "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." Photo: S. Lowe

A natural avalanche to the lookers left of the summit of Mt. Blackmore. 

From obs: "I noticed new debris coming out of the lookers left chute on Southeast face of Blackmore. got closer to the ridge and noticed this. happened last night or this morning. 5 feet deep 50 to 100 ft wide and ran roughly 800 feet." 

Photo: N. English

Avalanche triggered on 01/19. From obs on 01/20: "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 (01/19) morning from the summit. Ran all the way down to almost the skin track." Photo: N. English

We reached the east ridge of beehive basin at 11:30 and it was warming up quickly. We considered skiing east into middle just before the prayer flags, but when approaching the slope to dig a pit we got a significant collapse and decided to ski a more conservative pitch further north. When continuing north on the ridge we saw a recent cornice collapse which triggered an avalanche, size unknown but pictured here. The conservative east slope was in the shade and skied well.

on the way out we got another sizable collapse when skiing west down from prayer flags, on the shallow, sunny western slope, when I edged out of the gully at the first dog leg to regroup with the party. 

Skied two low angle meadow laps. Continued up towards Hyalite. Consistent whumphing when breaking trail. We dug a pit a bit before the first steep rollover on the way to Hyalite Peak (~9200’). ECTP18, broke 50cm deep where the storm slap interfaced with facets. Total depth 130cm. Consistent beefy storm slab underneath 4-5” of fresh snow once out of the thick trees. Snow so unsupportive we couldn’t walk 15 feet to dig our pit. 

we also observed signs of recent natural avalanche activity in Divide Basin

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. 

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! 

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. 

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.