Photos

From obs: 5/9/21: "Yesterday we went to check out the new snow in Beehive Basin... Looking down into the face of Peruvian, we observed a natural dry loose slide that released from the ridge... We observed an increase in wind speed throughout the morning, and a shift in wind direction from west to southwest in the early morning moving to west to north west by the late morning. The combination of variable and high winds with the amount of new snow available for transport created a noticeable increase in the hazard of wind slabs on all aspects we observed during the morning..." Photo: E. Schreier

From obs: 5/9/21: "Yesterday... While traversing... along the north ridge of 10602 [near Beehive], we triggered a small wind slab  that carried down into Peruvian, which then released another small wind slab on a northeast aspect of the face (photo). The crown height of this wind slab was measured at 60cm at it's deepest point, and approximately 30ft wide by 10ft long. Looking down into the face of Peruvian, we observed a natural dry loose slide that released from the ridge. We observed an increase in wind speed throughout the morning, and a shift in wind direction from west to southwest in the early morning moving to west to north west by the late morning. The combination of variable and high winds with the amount of new snow available for transport created a noticeable increase in the hazard of wind slabs on all aspects we observed during the morning..." Photo: E. Schreier

From obs: 5/9/21: "Yesterday... While traversing... along the north ridge of 10602 [in Beehive], we triggered a small wind slab  that carried down into Peruvian, which then released another small wind slab on a northeast aspect of the face (photo). The crown height of this wind slab was measured at 60cm at it's deepest point, and approximately 30ft wide by 10ft long. Looking down into the face of Peruvian, we observed a natural dry loose slide that released from the ridge. We observed an increase in wind speed throughout the morning, and a shift in wind direction from west to southwest in the early morning moving to west to north west by the late morning. The combination of variable and high winds with the amount of new snow available for transport created a noticeable increase in the hazard of wind slabs on all aspects we observed during the morning..." Photo: E. Schreier

From obs 5/9//21: "Yesterday we went to check out the new snow in Beehive Basin. We dug a pit on the south face of Peak 10602, and conducted an ECT with results ECTN8@20, ECTN11@30, and ECTN25@60. The new snow total in this location was 30cm. Although we saw no propagation, a hand shear test (photo) and a shear conducted on the remaining ECT block (photo) resulted in a Q1 shear at the interface at the bottom of the new snow. The bottom layers of the snow pack were wet from the rain that preceded the snow, and we noted that the crust below the new snow was soft and breakable and all aspects...." Photo: E. Schreier

Small wet loose slide that a skier triggered, running over an older crown from prior days. East aspect, 10,000'. From 5/7/21. Photo: D. Britt

Photo of a large natural wet avalanche in Taylor Fork, NNW aspect around 9,000' elevation near Koch Peak, on 5/3/21. Photo: D. Britt

From obs 5/6/21: "This morning we went to... the Tobacco Roots. The dusting of snow in recent days had wind loaded northwest aspects, and created a wet loose hazard by the late morning (photo). We observed several wet slabs that went at the ground on southern aspects throughout the area (unfortunately unable to get a photo), and temperatures were nearing 60F before noon." Photo: E. Schreier

From email 5/2/21: "Small but plentiful wet snow avalanches in Cooke City today. Didn’t see any that were broke on a deeper scale." Photo: K. Goodyear

From obs: "I traversed the Bridger range yesterday (4/28/21). The alpine start was good and solid but I saw lots of recent avalanches that looked super wet, some that had broken a couple feet deep. Conditions were pretty stable until about 1300 when that most recent snow layer started to really want to slide on the crust. Once I was in the meadows between Baldy and the M, at about 1400, I started hearing/feeling really wet "whumps". Photo: J. Harrison

From obs: "I traversed the Bridger range yesterday (4/28/21). The alpine start was good and solid but I saw lots of recent avalanches that looked super wet, some that had broken a couple feet deep. Conditions were pretty stable until about 1300 when that most recent snow layer started to really want to slide on the crust. Once I was in the meadows between Baldy and the M, at about 1400, I started hearing/feeling really wet "whumps". Photo: J. Harrison

From obs 4/28/21: "Observed numerous natural wet loose slides probably occurring over the past 48 hours on NW-W-S aspects mid-elevation. Point releases from rock bands and couloirs shedding. Photo for example, which shows W facing bowl with slides visible from US-89 in Paradise Valley. These are between 8500’ and 9500’ on an unnamed peak just northeast of Dexter Point." Photo: T. Benson

Natural avalanche of new snow on 4/26/21 in northern Madison Range. Photo: N. Truax

Natural loose avalanches of new snow ran on Monday 4/26/21 after 10-12" of heavy snow. Photo: A. Crawford

From obs: "[4/25/21] we toured up Sphinx mountain to have a look at the new snow. Both at the base of the west face and at the summit, new snow totals were approximately 5-10cm. On the approach, evidence of wind loading was minimal. Wind speed increased throughout the day, and we observed more significant wind loading on northern aspects. We found a supportable crust on all aspects of our ascent and descent and did not conduct any stability tests. Cracking on isolated wind loaded areas was observed on the approach. We did perform a ski cut on a northern aspect of the west face and on a western aspect below the face, and found that the new snow did not release. It seemed that low snow accumulation and lower temperatures kept the new snow in place on the Sphinx, but warmer temps and increased wind loading in the coming days may create a wind slab problem." Photo: E. Schreier

Loose snow avalanches run readily on top of the crust in the Absaroka Range south of Livingston on Tuesday 4/20. Photo: E. Schreier

From obs (4/18/21): "...class split and dug three pits, one on NE, one on N, and one on NW at 7623'. HS averaged around 70 - 100 cms... The NE and NW facing pits showed rounding depth hoar and no sudden CT results. None of the ECTs fractured or propagated. The N facing slope still had preserved advanced depth hoar 3 mm in size (see image)..." Photo: J. Quinn

From obs (4/18/21): "...class split and dug three pits, one on NE, one on N, and one on NW at 7623'. HS averaged around 70 - 100 cms... The NE and NW facing pits showed rounding depth hoar and no sudden CT results. None of the ECTs fractured or propagated. The N facing slope still had preserved advanced depth hoar 3 mm in size (see image)..." Photo: J. Quinn

Near Flathead Pass on 4/15.

From email: "We saw very isolated wind slabs near the top of the ridge but, with temperatures remaining below freezing, observed little activity in the most recent snow."
 

From obs 4/9/21: "...we saw widespread natural wind slabs on N-NE eastern slopes in the Northern Absarokas (photo). Winds increased throughout the morning, and evidence of wind transport became more apparent at higher elevations. We found that on aspects unaffected by wind loading, the new snow layer was not cohesive and only saw minor sluffing." Photo: E. Schreier

A small avalanche hitting the North Bowl Road.

Bridger Bowl is closed for the season and the ski patrol is on summer vacation. This means no one is mitigating avalanche hazards or closing terrain as conditions change, so skiers and riders have to make avalanche-related decisions for themselves and be prepared for partner rescue. It also means that familiar routes such as North Bowl Road may become unsafe. Photo: GNFAC