Spring avy danger warning?

Just saw this king5 story posted over on nwhikers;

www.king5.com/localnews/stories/NW_01220...ger_SW.49e683ab.html

Any thoughts on this? I am not as familiar with dealing with a snowpack like we have this year. Do you think those buried layers will consolidate by spring? Or will they persist and are there any good things to keep an eye on in that case? Will it be more of a danger on really warm days, mellow out by June, stay out of the sw chutes, etc?

Good questions, Ron.
When Paul Baugher and Mark Moore have something to say about it I usually pay attention.

I seem to recall a few years ago in May when a massive spring slide stepped down to the ground and cleaned off over half of Silver Basin at Crystal.  Seems like a couple of skiers were involved, too... maybe digging a pit or something.  I don't recall anyone being hurt, maybe just some gear lost or something like that.
Probably necessitated some pants to be cleaned up as well.

If memory serves, the typical buried ice crust (at least two [no three after last week] of which are present in our current snowpack) was the suspected initial culprit of that Silver Basin climax event.

As far as the SW Chutes goes, I think one needs to think about how the higher elevation plays into the likelyhood of the possibility of a similar persistent buried weak layer.  The chutes top out at about 11,500 and drop at a fairly steady angle down to 8,000 or so.  In addition they're facing directly into the most prevailing wind.  They also often tend to refreeze nightly.  My guess is those factors would somewhat cause one to think differently about them.  But I'm certainly no expert on the subject.  I do find that timing (especially time of day) and weather are most important to me when skiing such a long line.   They can get pretty slurpy late on a hot summer day.  I can recall a time (much too late in the day) when we had to ski cut across the entire line and let it wet slide to the bottom just to get a more solid bed surface to ski on.

In the KING-5 story Mark Moore is quoted saying: "It really depends on how the rest of the winter evolves. There's a lot we don't know yet." Mark knows a lot more about this than I do, but here's how I interpret what he is saying.

The two big questions in my mind are:

1. How much additional load will the snowpack get this winter?

2. When will the Big Warmup occur?

There are an infinite number of scenarios possible. Since it's impossible to predict what will happen, it may be useful to think about what would be the worst-case scenario. Here's my guess:

The winter continues to be cold and wet. Lots of additional snow loading is received, and we don't have any big pineapple express events to settle the snowpack during the winter. Then in the spring, warm weather arrives suddenly. It might be a big rain event or a sudden spell of hot weather. During this warmup, the snowpack goes isothermal for the first time and free water percolates down to the buried ice layer. BOOM - there go your really big avalanches.

Any variation from this worst-case scenario could reduce the risk of big spring avalanches, but it's hard to predict whether the risk is reduced "enough." Moderating influences could include:

- Warmer weather for the rest of the winter
- Lighter snowfall for the rest of the winter
- Progressive and gradual warmup in spring
- Cool spring weather but not too snowy

A rule of thumb that I follow is to watch out in spring when the temperature spikes higher than it has gone yet this year. If I have an ambitious trip planned, I often pass up the first really warm, fair weather period and shoot for the second nice window, provided that it's not a lot warmer than the first.

Interesting thoughts. I guess I was thinking along those same lines. That first big warmup with alot of rain may create some monster slides. And if conditions creates a situation for bigger than normal slides we could see roads getting hit that no one would think twice about driving on. The layers are scary looking in a pit especially when there are air pockets just hanging out under the crusts.

At least this part was relieving.

Statistical models show that the weather pattern -- colder temperatures and heavier-than-normal precipitation -- tends to occur more in the second half of the winter, he said.

"This is a historical year, and it's not over yet," Mass said.