Above-average temperatures today and tomorrow will create wet avalanche conditions. The main concern will be Loose Wet avalanches that occur as the snowpack heats up and becomes wet and unsupportive on steep slopes. Although the avalanches may be relatively small they can still pack a punch with the dense, heavy snow as they build up speed. Even a small avalanche can be dangerous if it catches you in consequential terrain and pushes you into trees or rocks.
The warm temperatures will also allow meltwater to percolate down into deeper layers of the snowpack. Upper-elevation northerly-facing aspects still hold a relatively dry snowpack below the top 12 inches or so, and as meltwater works its way down through the dry snow and saturates layers it creates the potential for large Wet Slabs avalanches on steep slopes. It’s difficult to predict the exact timing of when Wet Slabs will occur but warm daytime temperatures and consecutive nights of above-freezing temperatures are the kinds of conditions we look for to forecast them. If you notice upper elevation northerly-facing slopes becomes wet and saturated steer clear of consequential slopes until temperatures freeze and the snowpack solidifies again.
Since mid-April, we have documented a couple of layers of buried facets in the upper part of the snowpack on north-facing slopes. Avalanche activity on these layers has slowed since last week and the warming temperatures should help to put them to rest but that doesn’t mean they’re completely gone just yet. If you’re traveling to high elevation north-facing slopes and find 8 inches or more of recently drifted snow it’s a good idea to get your shovel out and dig down to inspect the snowpack for these layers of facets and avoid steep slopes if you find them.
Today is the last day of zone forecasting for the season, and what a wild ride it's been. We will continue to put out a regional forecast for the Northern, Central, and Southern Mountains each day by 4:30 PM for the following day. Be sure to stay tuned and check the forecast before you head out.