Friday 2/28/20 - Thursday 3/05/20
This week on As the World Terns: By Rob Millspaugh. Video summary by Zach Guy.
Last weekend kicked off with our warmest day of the year and subsequent Rollerballooza. We watched (some cheered) as thousands of rollerballs cascaded down around the advisory area. On some southern slopes these little guys were mercilessly wiped out by D1-D2 wet loose activity. Some cornices cracked and failed but many withstood this warming event and are still at large. Observers found windslabs, but these were resistant to the weight of a skier. A cold front on Saturday quickly cured the snow surface on sun exposed slopes into a stout (3/1) crust. Winds remained moderate through the weekend but had little snow to work with limiting windslab and cornice growth. Observers continued to find the 2/23 buried surface hoar and near surface facets in various locations, but lack of activity on this layer indicates it has gone dormant for the time being. High winds on Wednesday produced blowing snow and new windslabs. Southwesterly flow brought warm temperatures and clear skies on Thursday but the dearth of new snow limited the extent of surface wetting and wet loose activity. We received another report of a cornice-induced deep slab avalanche, this time from the Great Bear Wilderness. This is the picture you want to keep in mind when choosing routes in terrain where cornices are looming.
