The Canyons, Ut. (ABC4 News)- Amazingly, there have been over 100 man-induced avalanches in the past few weeks in northern Utah. No wonder ski patrols throughout the Wasatch have developed techniques to assess the current threat. Jake Hutchinson at the Canyons ski resort showed our meteorologist, Todd Gross, how to take a cross section of the snow., then mimmicked the pressure that a skier would put on the snowpack, using a shovel and tapping the snow.
The slab that popped out of the snow about 1 foot under the surface is like a miniature avalanche. It is the frosts (hoar frost to be exact) in between each snowstorm, that creates this slick surface for these slabs of snow to slip off. In other words, after the snow settles a bit, frost forms on the snow surface, creating less friction for the following layer above it. When the snow falls, it can "slip off" the old layer, and in fact, as this layering continues, there is often an unstable layer of snow that gets caught somewhere in the middle of the snowpack. Although the situation is improving, now, there are still at least two more major threats. First, this weekend, a heavy snowfall may reintroduce frequent avalanches especially in the southern Wasatch. Secondly, the very lowest layer of snow (that fell in later October) is already weak, and unstable, and may become more-so if rain seeps into it from above in the Spring.
