23-24

Weak Snow at Lionhead

Date
Activity
Skiing
Snowmobiling

We rode to Ski Hill and dug on a NE aspect at 8000'. The HS was 40 cm with the top 15 cm being from yesterday's storm. This soft new snow was sitting on a thick supportable crust, and below that crust was weak-faceted snow. Stability tests showed no results, ECTX. From here we transitioned to skis and began walking towards the Lionhead Ridge. As we increased in elevation the amount of new snow increased and we experienced small whumpfs and cracking as we approached the ridge. Below the ridge, we dug on a NE aspect at 8700'. The HS was 56 cm and there was 22 cm of new and wind-drifted snow on top of similar layering. We got an ECTP1 at the interface between the new snow and weak snow just above the crust. We saw no recent avalanche activity but another party reported seeing a small avalanche further along the ridge. 

Region
Lionhead Range
Location (from list)
LIONHEAD AREA
Observer Name
Zach Peterson

Shallow layered snowpack below Bradleys meadow

Date
Activity
Skiing

Skinned above alpine lift (just beyond the beacon checker) to get an idea for snowpack depth/ layers. A quick dig revealed a shallow, faceted snowpack!

 

Region
Bridger Range
Location (from list)
Bradley Meadow

GNFAC Avalanche Forecast for Sun Dec 3, 2023

Snowpack and Avalanche Discussion

<p><span><span><span><span><span><span>Prior to this weekend’s snow the mountains held a mix of dry slopes and slopes with up to 12-20” of old snow. During our recent dry spell that old snow became faceted and weak. I witnessed this in the northern Madison Range on Thursday (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=khUlf_rurog"><span><span><span><strong>…;), and Ian saw it a couple weeks ago on Sawtelle Peak (</span></span></span></span></span></span><a href="https://mtavalanche.com/node/29287"><span><span><span><strong><span><u>…;). Yesterday, skiers at Bridger saw 3” inches of wind-drifted new snow easily cracked on top of the old, weak snow (</span></span></span></span></span></span><a href="https://mtavalanche.com/node/29336"><span><span><span><strong><span><u>… and photo</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>), and Doug noted similar potential for avalanches while climbing in Hyalite (</span></span></span></span></span></span><a href="https://mtavalanche.com/node/29337"><span><span><span><strong><span><u>…;).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Near West Yellowstone and Cooke City got 12-14” of snow equal to 1.0” of snow water equivalent (SWE). This will create dangerous avalanche conditions, especially as more snow falls over the next 24 hours and where strong winds drift this snow into thicker slabs.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Carefully assess the stability of recent snow prior to riding or crossing below avalanche terrain. Avoid steep slopes where more snow fell, where new snow is drifted into thicker slabs, and if you see recent avalanches or cracking and collapsing in the new snow. Carry your avalanche rescue gear (beacon, shovel, probe) and make sure your and your partner's gear and skills are in working order.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Over a foot of new snow equal to 1.0” of snow water equivalent (SWE) creates dangerous avalanche conditions, especially where strong winds drift this snow into thicker slabs. Carefully assess the stability of recent snow prior to riding or crossing below avalanche terrain. Avoid steep slopes where more snow fell, where new snow is drifted into thicker slabs, and if you see recent avalanches or cracking and collapsing in the new snow. Carry your avalanche rescue gear (Beacon, shovel, probe) and make sure your and your partner's gear and skills are in working order.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>If you venture out, please fill an </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/add/snow_obs"><span><span><span><stron… form</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>. It does not need to be technical. Did you see any avalanches? How much snow is on the ground? Was the wind moving snow? Simple observations are incredibly valuable. You can also contact us via email (</span></span></span></span></span></span><a href="mailto:mtavalanche@gmail.com"><span><span><span><strong><span><u><span>…;), phone (406-587-6984), or Instagram (#gnfacobs).</span></span></span></span></span></span></p>

Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.

At 9,000 feet there was about an inch of new snow. It was calm at first light, but by mid morning winds were gusty and blowing straight down the gullies. It stripped what little snow there was and did not create an avalanche hazard. However, the 6+" in the gullies are all faceted, and with even a thin wind-load it was easy to get cracking. With snowfall predicted for the next 48 hours and again later this week, we'll need to be on the lookout for pockets or gullies of wind blown snow.

Northern Gallatin, 2023-12-02

Strong gusty wind moving snow in Hyalite

Date
Activity
Ice Climbing

At 9,000 feet there was about an inch of new snow. It was calm at first light, but by mid morning winds were gusty and blowing straight down the gullies. It stripped what little snow there was and did not create an avalanche hazard. However, the 6+" in the gullies are all faceted, and with even a thin wind-load it was easy to get cracking. With snowfall predicted for the next 48 hours and again later this week, we'll need to be on the lookout for pockets or gullies of wind blown snow.

Region
Northern Gallatin
Location (from list)
Hyalite - main fork
Observer Name
Doug Chabot

Shooting cracks on the Apron

Date
Activity
Skiing

Shooting cracks on the apron. Shallow and firm but reactive windslab breaking on the faceted layer bellow it. About 10cm of new snow sitting atop the windslab as of this afternoon. 

Region
Bridger Range
Location (from list)
Bridger Bowl
Observer Name
Charlie Bayles