Each storm continues to add weight to our fragile snowpack. This weight can be added from snow falling from the sky or the wind blowing the snow from one location to another. In any case, it just doesn't take much to stress the weak, faceted, old snow below.
It's a simple set up - we have a weak layer and a slab. There are two other critical components to triggering an avalanche; we need a slope steep enough to slide (generally greater than 30° in steepness). We need a trigger (skiers and riders make good triggers). These four components of a slab avalanche are good to know because if we remove any one of the components we don't get an avalanche. Unfortunately, we can't remove the slab and weak layer.
However, I can choose to ride slopes less than 30° in steepness with nothing steep above or adjacent to me and not trigger avalanches. For now, that's the only option we have, especially if we want to avoid being caught in an avalanche. Persistent Weak Layer avalanches are responsible for nearly 70% of all avalanche fatalities here in Utah.
Video: Field day in American Fork