Expect fresh wind slabs primarily on northerly and easterly aspects, but be aware that wind direction changed Sunday night into Monday blowing from the East and North which will redistribute snow to the sunny aspects of South and West. Upper elevations above tree line are of highest potential hazard, with recent extreme storm winds (W-SW) and snow totals reaching over a foot on Saturday/Sunday. There were some observations of skier triggered winds slabs 6-8” in depth Saturday during the storm in the Mammoth and the Virginia Lakes area. On Sunday, natural slab avalanches, some reaching the D2 category were observed in the McGee Creek/Nevahbe ridge area near Crowley. Local reports in the Mammoth area also described loose-snow sloughing in extreme and confined terrain, including some which would be enough to drag or injure a rider.
Approach the high country with care and focused attention on wise terrain choice both up and down this week. With Monday’s forecasted sunny skies and access opening up, conditions will be enticing to explore higher elevations of the zone. Keep in mind that you’re more than likely the first person up there this winter season and at this point, there is scant information recorded in the alpine zone. Be on the lookout for recent avalanches, blowing snow, recent cornice growth, and fat, pillowed snow surfaces. All these clues can help you identify and steer clear of recent fresh wind deposits and potential wind slab or new snow avalanche conditions.
Perform your own local assessments and be wary of terrain features that are conducive to capturing drifting snow such as the leeward sides of ridgelines, gully features, and cross-loaded depressions. More extreme terrain features such as steep, walled in couloirs and convexities will present some of the greatest areas of hazard or potential wind slab instabilities or loose snow sloughing.
Snow coverage across the zone is highly variable with the bull’s-eye for the deepest base being in the Mammoth area right now. Don’t lose sight that it’s still early and there are a lot of submerged obstacles and hazards everywhere. Keep It Real with terrain choice and focus on a season long program of fun to come.