Trip Planning for Butte Area

Today we checked out the Ramshorn Peak basin in the Tobacco Roots. We skied a northeast aspect on the southern ridge of Ramshorn and found isolated pockets of wind loading, and an ECT revealed an ECTN 16 @ 20cm (HS 145cm). A couple of hand pits collected on this aspect suggest that this windslab has the potential to move (Q2 shears with easy to moderate difficulty) with new snow or sustained warmer temps. The warmer temps were noticeably effecting the snow at lower elevations and direct south aspects. We observed small pinwheels increase throughout the day on southern aspects, and noticed a large cornice failure on the southeast face of Ramshorn. We found a small and protected wind drift on a southern aspect and, with relative ease, kicked off the cornice (photo). 

Snowmobilers reported seeing a large avalanche that appeared to have been triggered by a cornice fall on the east side of Mt. Evans in the east Pintlers, and it ran to the bottom of the bowl that most folks ride in at the head of 12 mile creek.    

Toured in the Flints this weekend on all aspects between 8-9k ft. Solar aspect had begun to develop a melt freeze crust. Consistent SW winds effectively transported the foot of low density snow which had fallen over the last week. Prevailing winds swirled off ridge tops and had begun to effect leeward slopes scouring and drifting below treeline. Above treeline, alpine slopes were primarily scoured with significant drifting noted in some leeward alpine basins. No significant signs of instability observed aside from isolated cracking of wind slabs on ridges.

Naturally triggered Avalanche on North North East aspect. Heavy wind loading evident. The slide appeared to be recent, 24 to 48 hours old. 

Tour up Maverick Mountain before they open for the season to check how the snowpack is shaping up in the Pioneers; snowpack representative of backcountry. Got a Christmas eve gift when 6-8 inches of maverick 'white thunder' (+/- 5% density) fell overnight adding 30-50% to the total depth of snow. Dug quick pit on SE aspect 8100 feet and there is about 12-16 inches of low density snow with poles and skis going to ground. Dug a little higher on NE aspect 8200 feet where the snowpack is about twice as deep; about 2 feet plus and has a soft-ish slab in the mid-pack. We performed stability tests. ECTP12 10cm off ground. Softer slab on top of loose faceted snow on top of a hard crust made for propagation in the extended column test results. Surprisingly no collapsing and minimal, very localized cracking right around the skis. Ski quality greatly exceeded expectations!

This is second hand from a reliable source in the Philipsburg ski/snowmobile community. Backcountry skiers on a north aspect near the Powell mine, North Flint Range, were digging a snow pit when the slope avalanched with the crown through their snow pit. Slab avalanche was estimated at 16 inches and slope was wind loaded. Avalanche ran 6-800 feet. Skiers stayed in the snow pit and no one was caught.