Colorado’s PWL

[timackie]

I have plans to ski some steep glaciers on multiple aspects (including north) early next week, but I’m a bit spooked by recent activity as well as recent and forecast snow.

https://avalanche.state.co.us/caic/o...p?obs_id=71638

Would one expect our persistent weak layer to behave any different on a glacial surface compared to a typical high alpine surface of grass, small shrubs and rocks?

Thanks in advance for any advice.

[Rudimatt7]

Glaciers in Colorado, where are those?

[MakersTeleMark]

Those are semi-permanent snowfields for people on crack.

Better rope up just in case.

[timackie]

I’m hoping to ski the St Vrain cirque. Six “glaciers” from 12:00 to 6:00 allow for a full day of fun, so I hear. Not glaciers by euro standards, but certainly a different bed and the potential for different interactions with the pwl from October. Thus the question.

The only ropes I’ll bring will be 3mm cord to hang the hammock and dry my socks.

[brutah]

I’m hoping to ski the St Vrain cirque. Six “glaciers” from 12:00 to 6:00 allow for a full day of fun, so I hear. Not glaciers by euro standards, but certainly a different bed and the potential for different interactions with the pwl from October.

They have different standards for glaciers in Europe? I prefer alaskan glacier standards, or possibly antarctic standards! Bigger cracks, the better!

But honestly, I would learn to evaluate snowpack in the field and not rely on a confirmation bias from an internet ski forum

one expect our persistent weak layer to behave any different on a glacial surface compared to a typical high alpine surface of grass, small shrubs and rocks?

I would be more concerned about the interface of the weak layer with the layers that are surrounding it and not pay much attention to what is under the snow. unless, you are concerned about basal facets

[MakersTeleMark]

Don't forget the glasses for the cirque.

[whipski]

aspect, elevation, weather, wind loading, slope angle and timing the usual suspects. some patrollers have been hitting big lines around here and elsewhere. historically I always waited till 3rd week of May for the pack to percolate like my coffee. my old worn out knees limit my approach hikes now so I prefer to 4-wheel as close to snow as I can get. San Juan's will be safer than the Zirkel's .

[Hacksaw]

You won't know the snow conditions until you get there. Spend some time poking around (i.e., digging).

[skiracer88_00]

This is a good question. I would imagine that the rotten base facets are still there overtop of the permanent snow. I would dig a pit and see.

You can identify if the facets are there with a pit, but assessing the risk of triggering a something that will step down to that layer is definitely not straight-forward and may be impossible with any field test.

[timackie]

Thanks for the advice. I was hoping a pro would say, “Of course the base facets are not an issue on a permanent snow field, dummy. Every one knows that.”

On snow evaluation sounds great, but I don’t want to lug stuff for a 3 day trip 9 miles to then have to make a good decision. That’s a good way to make a bad decision. I was hoping for a consolidated spring snow pack to feel safe on those slopes, but it isn’t here yet.