Regional Conditions for Northern Madison

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 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

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

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

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

Skiers had a collapse which made this crack on a south facing slope with a shallower, wet snowpack around 9,000' near Cooke City. Photo: J. Redfield

This wet slab was reported on 4/4/21 around 8,200' elevation in the Main Boulder drainage south of Big Timber, outside of our advisory area. It happened that day or very recently during extended above freezing temperatures. Photo: G. Smith

Some of the wet loose avalanche activity around Beehive Basin is getting large enough to be dangerous in its own right, other activity is dangerous because it could push us into hazardous terrain. Photo: GNFAC

Some of the wet loose avalanche activity around Beehive Basin is getting large enough to be dangerous in its own right, other activity is dangerous because it could push us into hazardous terrain. Photo: GNFAC

Extreme winds on 3/28/21 transported snow that fell over the past week into fresh wind slabs. Photo: BSSP

From obs 3/28/21: "Saw this slope which frequently slides had been triggered on our way out last night [lower left in photo]. Slid to the ground but I expect it was mostly new snow as there is a larger old crown visible further uphill... I did see two other small pocket slides yesterday also in new snow on bed surfaces of older slides... General snowpack is getting very deep now but a thick junk layer remains at the ground everywhere I dug sleds out." Photo: J. Gerardi

From obs: "Deep slab avalanche in Blackmore Basin that appeared to break on the depth hoar near the bottom of the snowpack. It was on a wind loaded NE facing slope at approx. 9,500 and looked to break on a slope in the 35-40 degree range. The crown was about 8'-10' deep and 200' wide. It broke to the ground and ripped out several small trees." Photo: JR Mooney

Small snowmobile triggered slide in the new snow on Buck Ridge. Likely triggered on 3/26/2021. Photo taken 3/27.

Photo: GNFAC

From obs: "On Friday, my partner and I went into Middle Basin with the objective of skiing Middle Peak, and possibly the short couloir that splits the face. That morning we dug a pit on the east facing aspect of the beehive/middle basin ridge (ECTx). Encouraged by our results, we continued on to the base of middle peak and dug another pit (ECTp 30) on the south-facing ice crust. We continued on to summit middle peak and ski down the face to the entrance of the couloir, we descended 20ft into the entrance on soft loose snow and dug our third pit (ECTx), we replicated our results and decided the feature would be safe to ski. At ~1pm the first skier descended the slope, and triggered a small windslab (4-8in and 20ft wide) about 100ft down the slope and skied away uncaught. Skier 2, descended a lower angle slope to the east."

Ian and Dave stop to do a quick stability test as they hunt for a layer of weak snow 1-2 feet under the surface. Photo: GNFAC

From email: "We both set off some small sluffing on the west side of the ridge between Middle and Beehive on our way out; the snow on that aspect was a lot thinner and more prone to sliding on the older icy crust under the new snow. Photos are from below where we skied out; we dropped onto the west-facing slopes maybe 100' south of the prayer flags." Photo: P Calabro

From obs: "On our way up the summer trail route to Hyalite Peak our party of three remotely triggered a small avalanche from the skin track at around 9,600ft on a east facing aspect. The storm slab went about 4 inches deep and 150-200ft across a small roll over feature. We were about 150ft away when we triggered the slide." Photo: C. Kussmaul

Skier triggered sluffs on Fan Mtn. Small wet and dry loose avalanches were triggered depending on aspect/elevation. 3/18/21.

Photo: H. Coppolillo

Deep slab avalanche on Arden Peak at the back of Maid of the Mist basin in Hyalite. Probably broke between Feb 22 and Feb 28, 2021 Photo: GNFAC

Seen from near Ennis on 3/4/21. On Finger Mountain in the southern Madison Range. Photo: D. Frohman

From obs 3/6/21: "Two large natural avalanches in Maid of the Mist Basin. One of them ran on the east face of Arden Peak (Peak 10,201) which propagated across the entire face. Could have been triggered by a cornice fall then stepped down to deeper layers. The second was on the NE face of the peak Fat Maid and Skinny Maid come from. Also propagated across the entire slope. Crown height between 6'-8' in most places." Timing of these slides is unknown. Probably in the last week, but maybe older. Photo: S. Enloe

We saw these recent wet loose avalanches on 3/6/21. SW aspect, 9,100'. They likely ran during above freezing temperatures between 3/3 and 3/5. Photo: GNFAC

From obs: "Small D1 avalanche on south-eastern aspect around 7800ft. Looks like solar released on older layer a day or two ago."

Photo: M. Mailly

From obs: "While touring above the canyon this morning, I noticed a very recent wet slide (would guess this incident occurred yesterday afternoon, March 4th). This was a skier triggered slide on a E aspect at an elevation of 7200. This slide was roughly 50 feet wide and ran about 50 feet, I estimated this crown to be 2-3 feet deep, slid all the way to the ground. This occurred below a steep roller."

Photo: T. Saulnier

"On the drive back we saw a large crown on the NW face of Big Horn peak..." (likely broke Sat or Sun, 2/27-28). Photo:  S. Jonas

Wet loose avalanches released in the warm sunshine on Tuesday, March 2nd. We expect many more in the coming days. Photo: S. Jonas

Small loose wet avalanches on Buck Ridge (3/2/21).

Photo: GNFAC

Natural avalanche near Cedar Mountain. 3-4 feet deep. Observed on 3/2/21, likely broke around 2/23 or 2/24.

Photo: GNFAC

Overview of the slides triggered by skiers in the 3rd Yellowmule on Sunday 2/28/21.

Photo: GNFAC (3/2/21)