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  • Summer Avalanche Safety

    Hi all - hope the summer is going well

    I've admittedly struggled with summer avalanche safety ever since I started going into the backcountry to ski. CO winter snowpack is straightforward in the sense that it's so full of uncertainty, and spring snowpack is consolidated through it's freeze-thaw and as long as you get it before it's a mess from the sun, you're typically good.

    Summer throws me off. Oftentimes even the highest lines in CO aren't freezing much in June, even at the top. And 2000 feet down you can bet it might not have frozen in days. But the snow is also often very solid from the processes it's gone through as the seasons change.

    I've had one 'interesting' summer skiing experience in particular that made me think pretty hard, so I'm usually done skiing by this time, but the crew has some possible destinations the next few weeks. Do you all feel pretty safe as long as you are off of the slopes early in the day in the summer? Since the snow has changed so much? Or do you all play by the standard rules: hope for overnight freezes, and if days go by without one, stay very conservative and cautions? I presume avoiding rockfall areas is top of mind as well with such a hot sun. I've never gotten very clear answers on the summer snow like the spring (and maybe the answer isn't very clear to begin with) so appreciate feedback.

    Thanks

  • #2
    Strangely enough several people climbing Dead Dog Couloir on Torrey's ran into trouble yesterday, glad all are okay
    The Clear Creek County Sheriff's Office responded to a report of an avalanche on Torrey's Peak Sunday morning.

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    • #3
      I'll be a little controversial and say Dead Dog sucks. I made this comment on a thread about this incident on CAIC's Facebook page and got laughed at. What I said was it is a shooting gallery. And you are likely to be dropping in on snow climbers who just bought all their gear at REI and are using it for the first time. Yes, it is a striking line and it is right in your face. But there are a lot of better places to either ski or climb.

      The further we get into the summer, the more confident we can be about avalanche conditions. I am speaking specifically about Colorado, so let's not extrapolate this to other snow climates. As we move into summer, the concern becomes more about the consequences of falling. I will add that it is not summer yet, neither by calendar or climate, and this snowpack is still evolving.

      Conventional wisdom and Level 1 courses always teach that the first non freezing night in spring is a bad time to be out. And while I don't disagree with that, I maintain that it is the 3rd, 4th, or 5th consecutive non freezing nights when all hell breaks loose. But even while all that liquid water is present, destabilizing the snowpack by lubricating ice lenses and destroying bonds between crystals, water is also draining out the bottom. The snow does continue to consolidate as that is happening. There will eventually be a lot less of it but what is left will have gained strength as internally, it can still freeze and bond even when the air temperature does not go below freezing due to radiational heat loss on clear, calm nights.

      You are always wise to be off the mountain by noon and also wise to be aware of sun angles and early morning solar radiation. Remembering that the summer sun rises to the north of due east, look at north facing slopes as places that heat up first. Look out for wet slabs in the northeast facing sides of north facing gullies.

      East facing slopes that have only seasonal snow on them--like Dead Dog--sometimes never consolidate and can produce wet slabs until they are bare ground. Also, ALWAYS look at lines from the top down with an eye on what can possibly fall on you, where it comes from and what path will it take.

      Paradoxically, south facing slopes that are heavily wind loaded thought the season can be more stable because they have had the benefit of more and earlier melt-freeze cycles and do not get hit with direct sunlight until later in the day. This is especially true if they have permanent snowfields on them so that the ground is not providing a heat source through the winter driving constructive metamorphism, i.e., faceting and depth hoar development so the seasonal snow is bonded to previous years' firn. Skyscraper does not even become easily accessible until July and even then, a big mandatory cornice huck can mean we have to continue waiting.

      West and northwest facing lines, while rare, are usually more consolidated for the first two of the reasons south slopes can be attractive. Think the Tuning Fork on Torreys or northwest facing couloirs off Elbert.

      Summer skiing in Colorado is one of my favorite things to do. I really miss it.
      Last edited by cesare; 7 June 2021, 03:51 PM.

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      • #4
        Don’t overthink this Cesare

        … yer goin to die! 😎

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        • #5
          I said I was speaking specifically about Colorado. It's nothing like a maritime snowpack.

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          • #6
            Ya gotta know your snow anytime you ski Coloweedo backcountry. The Front Range received a heavy wet dump in early March, 2021. That totally changed the snowpack from sketchy to stable - at least North of I-70. However, cesare's basic advice is correct, arrive early, and be off the slope by noon (if not for avy danger, then for lightning danger). However, daily changes in temperature need to be watched. Skied Cameron Pass a week ago and the snow was perfect spring corn. Quite amazing for CO, but the temps were right - the skies were clear in the preceding days and the day I went it dropped to 30 overnight. The snow didn't ripen until 10:30. If the snow feels soft and mushy when you start at the trailhead, it's too warm and the odds of a wet slide are high.


            Click image for larger version Name:	1-run_corn-pass_1192.jpg Views:	2 Size:	290.1 KB ID:	110231




            ain't no turn like tele!

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            • #7
              Originally posted by JackO View Post
              and maybe the answer isn't very clear to begin with
              This is always true, because avalanche science is rarely a single variable equation where you check one parameter and you have a clear decision easily made. I always liked the idea of calculating risk as a percentage, and accepting that there's never a time when the risk is zero... That keeps you from turning your brain off and concluding things are totally bulletproof at some point in the season. You always need to be observing and calculating the odds of the problems you think are possible. Some of those indications are observable in the field, some of those indicators are in the telemetry data. My strategy is to keep track of my local snowpack all season, and check telemetry every time there's a new weather event looking for things like high winds and wind directions as well as the obvious snowfall depth, etc.

              I'm not familiar with typical continental colorado avy cycles. I'd be scared to death touring down there without an experienced local because If you ski an area enough over a long time, you get the benefit of seeing the typical scenarios play out over and over on familiar terrain. I think that is worth a lot when it comes to making judgements, but I guess it has also lured some into a false sense of security too.

              In my own area, I track the weather data every season and keep a running notation of the instabilities in the winter snowpack as they occur. When the spring hits, we usually have a bombproof base due to multiple thaws and refreezes, so we mostly only have to worry about changes from the most recent weather events until the heat of oncoming warmer weather begins the climax avalanches. Then, everything that is going to drop, drops due to temperature. It's hard to miss that event because evidence begins to show up everywhere, and is usually caused by a noticeable warm spell.

              I felt like it took me 10 years traveling in the backcountry in my area before I was comfortable "most" of the time.
              Last edited by tele.skier; 8 June 2021, 11:48 AM.
              the fall line is your friend.... resistance is futile

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              • #8
                Originally posted by JackO
                You over at Diamond Peaks the other week there Dostie?

                The mush rule is a good rule, I imagine if you're on a firm snowfield even though it's warm/summery the snow probably won't be going anywhere.
                Sssshhh. I admit to nothing.

                ain't no turn like tele!

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                • #9
                  How are you Westerners holding up to the avalanche of hot weather?

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