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Triggering wet snow avalanches will become increasingly likely with today's first round of sustained sunshine since recent storms. Expect these slides to become large and destructive in big terrain, moving fast on slick crusts. Be wary if the snow you are moving through becomes moist. Pockets of wind blown snow can still be triggered in exposed, upper elevation terrain. Cracks shooting out from your skis or machine are a clear sign of an unstable slab.

Today will bring sustained sunshine to the snowpack for the first time since our recent wet and wild storms. There is a thick sun and rain crust beneath our recent snow at middle and upper elevations. The snow that accumulated on top of this crust has started to melt and bake on, but will be shed easily today when the sun returns in force. While it will take a bit of time for things to really warm up, once they do we will see quite a bit of shedding, likely lasting through the day and following the sun around the compass. Anticipate wet loose slides to become large and destructive in large terrain. Slides running on top of the crust will move fast and far. The recent snow has settled into a dense slab in many locations and these surface slides may flank out and have a slabby character to them. While this describes our wet snow problem, high rain lines and shifting rain/snow precipitation patterns during an intense series of storms last week leave more uncertainty in other portions of the snowpack. When you head into the mountains today you will find wildly variable conditions as you climb in elevation and change aspects. Read on. 

At lower elevations, the majority of the recent moisture fell as rain, with a few inches of snow at the tail end Friday and Saturday. The snowpack here has had some time to drain and refreeze and triggering large slides at lower elevations is unlikely. However, if you're encountering a wet, mooshy snowpack, think about the consequences of triggering small wet snow avalanches.

As you climb into middle and eventually upper elevation terrain, you will see snow totals increasing significantly. Most of our upper elevation terrain stacked up 2 or more feet of snow since Wednesday. Strong winds blowing out of the S/SE accompanied precipitation initially. Winds picked up a bit yesterday and shifted to blowing out of the NW. A new generation of wind slabs built in upper elevation terrain. These fresh slabs will be easier to trigger but much smaller than the huge slabs that formed on Thursday. The older, much larger slabs have had more time to bond and will be less likely to slide. However, at upper elevations where these slabs rest on weak surfaces like facets and crusts they may remain reactive. As a reminder: skiers in the Boulders (on Galena Peak and Lorenzo) were triggering small wind slabs at the start of last week, before therecent storms. 

Manage the complexity, variability, and unpredictability posed by our transitional snowpack by building a wider safety margin into your travel plans today. Pay attention to the snow you are moving through, the snow on the slopes above you, and the snow you will have to move back down through at the end of the day. Pay attention to how much snow is being melted. Be ready to step back from the plans you make, and have an exit strategy if things start to melt down. It may be springtime, but we are not at LOW danger just quite yet. The spring transition period is one of the easiest times to get complacent: the weather is friendly, but the snowpack still demands respect and attention. Don't take the sunshine as an invitation to turn your brain off.