Flathead Range & Glacier NP

The primary hazards today are crusts, firm or breakable, and wind-hardened snow up high. You may find punchy mank at lower elevations. Exercise normal caution and good backcountry travel techniques. Carry rescue gear that you know how to use. Ride with a competent partner who will keep you in sight. Only expose one person at a time, or avoid, large avalanche paths or overhead hazards like cornices. 

Observers on Friday had two main points to share: 

First, avalanches ran earlier in the week. A surprising amount of new snow coupled with moderate to strong winds created reactive slabs of new and drifted snow on Tuesday and Wednesday. Above freezing temperatures, and rain, initiated a loose wet avalanche cycle on Wednesday. Ample sunshine and a lack of overnight freeze made the problem worse by Thursday afternoon. Most reported avalanches initiated below about 6,500 feet. Hard wind slabs and cornices were stubborn at upper elevations on Thursday. No one saw new avalanches on Friday. A few glide cracks seem to have opened up where the ground cover is smooth, but none of these appear to have released as avalanches.

Second, crust and wind-hardened snow at the surface has made riding conditions challenging. Comments like “not powder,” “comical skiing,” and “Crusty McCrusterson” pepper our observations page. Crusts, thick or breakable, cap the snowpack to at least 6,600 feet. Underneath, the upper snowpack is dense and settled. Layers of weaker, faceted snow lie in the middle of the snowpack and near the ground above a crust buried in early December. We have not seen enough warning signs in our region to list these layers and a persistent slab problem. However, destructive avalanches failed on old facets and crusts over the past week up near Fernie, BC. Those avalanches initiated on rocky, southerly slopes with shallower snow cover.

Surface hoar and near-surface facets have developed atop the crust in some places. If you are braving the crumby conditions, please tell us if you find one of the notorious weak layers at the surface before snowfall covers them.

Have a look at the updated Conditions Blog. Our intern, Rick Ziegler, and lead forecaster, Mark Dundas, have done an excellent summary of the week.