23-24

Skied north of Cooke City the last couple days ( Sat. 4/27 and Sun. 4/28), near Lulu Pass and Henderson Mtn.. Yesterday there was 2-3" of moist new snow, and the snowpack below had not refrozen up to 9500-10k', it was very wet and unsupportable below the new snow. Moderate east wind yesterday drifted the new snow into small slabs up high.

Today there was 1-2" new snow on top of a thin, breakable crust around 9,000', with wet unsupportable snow below the crust. The crust softened quickly in any sunshine midday. Pulses of heavy snow mixed with periods of partial sunshine and calm-light wind.

Saw only small slabs crack beneath skis along the ridge yesterday, and minimal wet snow avalanche activity. Despite minimal observed avalanche activity, it seemed like a skier or rider could trigger a larger wet avalanche, especially on slopes that received sunshine.

Photos attached of what appear like wet slabs possibly from Friday when the precip. started after the first night or two of poor freeze (North side of Republic, and Henderson Bench).

"We toured to Elephanthead Mountain today (4/27/24). Most of the couloirs emptying into Mission Creek (e.g. Das Ist Ice, Pitchfork Couloirs) showed signs of recent, large scale wet slides. Higher on the mountain, we observed fairly recent avalanche debris and crowns of 4-5 feet. On our descent of Mission Creek, we crossed large, wet slide debris fields that buried our earlier skin track (see pic). Our decision was to stick to low angle terrain and to steer clear of runout zones of any couloirs." Photo: T. Kalakay 

Rain below 7500-8000' the last 3 days.

We toured to Elephanthead Mountain today (4/27/24). Most of the couloirs emptying into Mission Creek (e.g. Das Ist Ice, Pitchfork Couloirs) showed signs of recent, large scale wet slides. Higher on the mountain, we observed fairly recent avalanche debris and crowns of 4-5 feet. On our descent of Mission Creek, we crossed large, wet slide debris fields that buried our earlier skin track (see pic). Our decision was to stick to low angle terrain and to steer clear of runout zones of any couloirs.  

We toured into beehive today starting at around 7:30 AM. We found about 2-4" of fresh wet and heavy snow. Lightly snowing all day until we left around 12 when the snow picked up a bit. Passing fog in and out all day. Around 9400' we dug a pit to the ground (east facing). ~95cm deep. We found about 5" of thick snow from the last two days, on top of a thin layer of graupel and ~4" of very wet snow that had not refrozen from the previous warm-up. The rest of the snowpack was also wet to the ground, but not to the same extent that the upper couple of inches were. Near the ground was definitely a weaker structure, but was also now saturated and closer to "corn snow" than anything. Also noted an ice layer about half way though the snow pack. 

In our pit we got cracking in the new snow (ECTN9) and in the top (8-9" down) of the saturated snow pack (ECTN18), but no propagation. A shovel shear test revealed our two layers being about 8-9" down at the bottom of the very wet layer, and at the interface with the ice layer halfway down. No collapses were observed. No avalanches were observed. We got some sluff while we were skiing, but only when skiing/hop turning aggressively. We chose to ski some steep and short couloirs.

The skin track had decent coverage besides a few spots in the trees. It was rain mixed with snow in the parking lot around 12:45, which quickly turned to rain as we drove towards big sky.

Snowpack had no freeze up to 10K' last night, poor freeze last 2-3 nights.

On 4/26/24 large natural wet slabs were seen running on Wall Mountain near Silver Gate. An observer from Beartooth Powder Guides sent us a video of them happening at 3pm while it was 43 degrees F. I also noted a similar large crown on the north side of Republic Mtn. that probably also happened this afternoon. Photo: GNFAC