Snow Observations List

We skied near Henderson Mtn. and Lulu Pass. Skies were clear with a light breeze near the ridgelines. Temperatures stayed below or just barely above freezing.

We saw a couple 3-6" deep natural wind slab avalanches and a few dry loose slides that looked to have happened within the last 24 hours. On southerly slopes below 9,000' there were some wet loose slides from yesterday afternoon. 

Wind slabs were still reactive today. We triggered 3 small, 3-8" deep x 5-15' wide, hard wind (1F+) slabs on convex test slopes well below the main ridgelines. 9,800', NE aspects. Also triggered one softer (4F) wind slab just below the high ridgeline, 10,200', NE aspect. 10-15' wide x 6-8" deep.

Snow stayed dry on northerly/shady slopes. Any sunny slopes got moist and had a crust formed by late this afternoon. We did not notice any fresh wet loose slides or roller balls on southerly slopes above 9,000'.

Stay alert for unstable drifts of snow, wind slabs formed last week are still breaking. Anticipate wet snow hazards to increase in size and distribution as the days get hotter this week.

We snagged an early morning tour to avoid the heat today and it (mostly) worked. We saw no avalanches, cracking or collapsing while out. 

-We found a 2-4cm thick breakable crust on SE, S, SW, and W aspects that probably formed during Friday’s sunshine capping 6-10” of fresh snow above 9k’

-There was much less fresh snow below 9k’ (baked off?)

-Northerlies held stable soft snow!

-Small natural dry loose activity started around 11am on steep NE and E slopes initiating from around rocks/trees

-We sniffed out some south facing corn, but it was generally grabby/sloppy wherever a few inches of recent fresh snow remained

A snowobarder tagged us in an IG story of triggering a long running, powerful wet loose slide in the Bridger Range.

We went on a tour in the Bridgers today, we ascended the east ridge of Naya Nuki to the entrance of the Great One. Wind was blowing and we were being careful about potential wind slabs up high.

Skier 1 ski cut the top of the chute and produced a small wind slab that ran to the break in the chute and continued another 100 vert down the east apron. After all meeting up halfway down, skier 2 proceeded to ski the E facing apron. A wind slab propagated and carried skier 2 roughly 300 vert down the apron where skier 2 was able to swim out of the fall line and came to a rest on top of the debris. Everyone was okay aside two missing ski poles.

On the way out, we saw a few more small natural wind slabs that broke naturally near ridge lines as well as point and release wet slides.

From BBSP: " At 2.45?pm a... solo skier triggered a wind loaded pocket on the main face of Saddle Peak that ran down over the cliff and produced an impressive powder cloud.... I met him... and confirm he was alone and no one was in front of him. The avalanche looked to be 2' deep on the southern flank and 5" deep on the northern flank... It entrained more snow on the way down, one 2' deep downhill wind loaded pocket and some loose wet snow. It ran into the bottom of the going home chute, gouging a large hole and then 100ft downhill left a 200ft by 30ft wide shallow debris pile."

Observed multiple D1-1.5 natural dry loose avalanches (and some tiny wind slab pockets under the ridge cornice) that likely occurred during peak warming around 2-3 PM. North/sheltered aspects from ~9- 8.5k held an average of 8+ inches of dry, drifted snow. Early AM to mid-afternoon, very active wind transport followed by tapered winds and a rapid increase in temp. Also observed one small wind slab occurring between Saddle & the Football Field, possibly skier-triggered.

Wind slab near Cooke City from yesterday.  Intentionally triggered.  North aspect, 10,100'.  1' deep, 20' wide.

I was skiing in bounds on Slushman’s lift and saw a pair of R1, D1 avalanches on Saddle Peak. One appears to be a loose snow avalanche triggered by a skier coming off of north Saddle Peak That ran a couple hundred feet. The second was a small slab coming out of Spencer’s with debris running into Going Home Chute. 
 

There were many tracks across the visible Saddle Peak terrain. 

My ski partner and I toured up Ellis today and skied the typical east facing gullies. 

We found the new snow to be bonding well to the crust and no significant instabilities within the new snow. Light snowfall off and on throughout the day, total accumulation no more than 0.5in, sky broken to obscured. Excellent skiing above 7K

Skied around Beehive Basin today; there was lots of new snow and very little wind effect. Skied into the top of Bear Basin from Beehive by going up going home and down the east side, right-side-up powder skiing. While descending Island Boy into the South Fork of Spanish Creek, we had similar 60-100 cm of right-side-up new snow on a heavily textured melt-freeze layer of old snow. Felt the snow density stiffen up from light low density snow around 300 meters down the ski line so cut to the left into a safe zone, the slope at the my skis broke about 15-20 meters wide and 15 cm deep at the flanks to 40cm deep in the gut, SS-ASu-R1-D1.5-I-M(L)-TK. About 30 meters downhill, the slab rode up onto the new snow and ran out of momentum before reaching the runout. Right where the slope broke, we had wind wrapping around the north ridge cross-loading the couloir (skiers left to right), downslope, and on skiers' right of the line, there was no evidence of wind transport. Skied the rest of the line and looped back into Beehive with no other excitement. 

Ice Cream Scoop on Skiers Left Side in Gully, North Aspect, 9280'

SS-ASu-R1-D1-S

One of the few spots on the gully where there are no trees as a wind block on the skiers left (south) side. Noticed a few cornices on south side of gully where it is exposed to W/SW/S winds. Skier took a left turn under cornices to scrub speed and released a 6-10" windslab 40' wide which ran 10' at most. Super soft and easy to ski through. 

We rode Buck Ridge through First Yellowmule, Buck Creek, Second Yellowmule and into McAtee Basin. Pulses of snow through the day dropped an inch or two by the time we left. Light winds, no avalanches, and no signs of instability to report. The measured storm total above the melt-freeze crust was 11" (1.3" of SWE) at the top of 1st Yellowmule. The snow was well bonded to the underlying surface. Quick pits testing the snow above the melt-freeze crust yielded no indicators of instability. 

The riding was quite nice other than the lowest section of the Doe Creek Road is melted out. It was fine on the way in, but very muddy on the way out. 

Triggering an avalanche is unlikely UNLESS:

1. The wind picks up to speeds capable of transporting snow. 
2. The temperatures increase or slopes get hit by the warm spring sun. 
3. There is another significant pulse of snowfall. 

From email: "Ski touring near Cooke City today we intentionally triggered a storm slab/ wind slab on a steep north aspect around 9600'.  It was about 6" deep, and 30' wide." 

We skinned up to the Beehive-Bear ridgeline, down into Middle Basin, up Middle Peak and returned the way we came. 

It snowed on and off all day, with little accumulation and patches of sunshine mixed in. Winds were moderate at ridgelines and light-calm lower down. During the periods of sunshine we had good views into Beehive and middle basin. We saw no recent avalanches or signs of instability. 

There were 10-12" of new snow from the last couple days above firm crusts. The new snow had bonded well to the crust. We encountered a little wind drifting at the ridgeline, but it hadn't formed much of a windslab. Loose dry sluffs were the biggest hazard we encountered. The little bit of sunshine densified the snow surface and caused roller balls, but wasn't enough to increase the hazard. 

We headed out to the Bridgers this morning with 13" (1.4" SWE) and more on the way. It may have been April Fool's Day but this was no joke - it is deep out there! We rode out to the Throne and made our way up the East Ridge. On top of the foot of fresh, it snowed around 3-5" in the three hours we were out there.

Our main concerns today were dry loose, storm slab, and wind slab avalanches. We were able to trigger small, loose snow avalanches on steeper slopes in the upper 6" of snow. In one steeper roll over, I got shooting cracks and a small storm slab to break at my ski tips. We did not see other cracking in the recent snow. Visibility was very limited, but we saw one small, filled-in crown near steep, rocky terrain just above the top of the Throne. Winds were blowing all day but were not noticeably drifting snow at mid-elevations. 

When we dug down and performed quick stability tests, we got a mix of ECTNs and propagation (ECTP 10, 11) on a hardness change within the storm snow about 12" deep. We noted this hardness change throughout the day. At lower elevations it was only 3-4" deep, while at upper elevations, closer to a foot. 

Lower down on the E Face, we saw a glide crack that had opened likely after the warm temperatures from last week. 

Heavy, wet slide of recent snow released while skiing off South Saddle. Photo is from South Central.

Winter conditions in middle basin. Cracking in wind drifted pockets at the top of bat ears couloir and at the top of middle peak. Snowing hard all afternoon nearly filling in our skin track by the time we exited. 

Skied Hellroaring Hut in the Centennials from Friday Mar 28 through Mon Mar 31.

Skied and observed all aspects between 7700' and 10,200' in the vicinity of Mt Jefferson and Reas Peak.

We had good visibility for three days and saw no signs of slab avalanches; no whumphing or cracking; and no signs of blowing or drifting snow (prior to new snow arriving today (Mar 31) snow surface was locked up with solid melt-freeze crusts on all aspects and elevations).

Snow surface starting to show meltwater runnels on S through E aspects below 9000'.

Test pits on N and S aspects at 9100' revealed moist snow under melt-freeze crusts (3" thick breakable crust on N aspects; 10" thick stout crust on S aspects) and no identifiable layers of concern in the upper 130 cm of the snowpack. HS 165 cm on S aspect at 9100' and HS 260 cm on N aspect at 9100'.

We observed pinwheels and predictable wet loose avalanches (D1 to D1.5) on solar aspects above 8000' on Fri and Sat.

Snow started this morning (3/31) and 2.5" of new snow had accumulated when we left at 11:00 a.m. Moderate to strong winds blowing from the south today.

Shooting cracks in wind drifted snow on the northwest side of Miller Ridge, and wet loose slides on the southeast side. Very variable out there. 

The skiing was good and non reactive on the main East face next to the skin track. The North gullies into Naya Nuki creek and the the lower/steeper gullies to the south were highly reactive and entraining lots of snow.