Turnagain Pass

A low pressure system sitting over Prince William sound is expected to bring light snowfall to the area today, with increasing northwesterly winds as the system passes and outflow winds pick up behind it. Snow totals are looking to be around 1-3″ for most areas, with winds around 15-20 mph at upper elevations by this afternoon. The combination of a few new inches of snow on top of last week’s storm snow will provide plenty of ammunition for the winds to build reactive wind slabs. Since the winds will be coming out of the northwest, they will be more efficient at picking up snow from cold and shaded slopes with dry snow at the surface, and load it on southerly slopes with crusts at the surface. This will most likely mean fresh wind slabs may be more reactive than usual, and they may hang around a little bit longer than usual.

Wind slabs forming today might not be huge, but they may be approaching sizes large enough to bury or injure a person. Keep in mind even small avalanches can have serious consequences in big terrain, and choose your terrain accordingly. Be on the lookout for telltale signs of unstable snow– shooting cracks, collapsing, and fresh avalanche activity. Because of the way local terrain channels winds, these northwest wind events can have some funky wind patterns in the Turnagain Pass area. This pattern commonly results in northern winds along the motorized side of the highway with southerly winds along the skier side, and winds can switch directions as you gain elevation. Be on the lookout for wind slabs potentially forming on all aspects today, and take the time time to assess stability before getting into steep terrain.

Glide Avalanches: We are continuing to see glide avalanches release in the area, with the most recent activity along the Seward Highway yesterday just north of Girdwood. These avalanches are very large and unpredictable, so limit the amount of time you spend under them.

Dry Loose Avalanches: For slopes that stay protected from the winds, pay attention to sluffing in steep terrain. These may be easy to trigger and fast-moving on southerly slopes where new snow is falling on firm surfaces.

Northwest outflow winds are on the way. Winds should start picking up this afternoon, with sustained speeds of 15-20 mph by the end of the day. Source: NAM model on Windy.com.

The weak interface that was buried on April Fool’s day is becoming less likely to produce avalanches, but should still be on the radar today. The most recent avalanche activity on this interface was a skier-triggered avalanche on a northeast-facing slope in the Seattle Creek drainage on Monday. Keep this layer in mind while navigating the mountains today, and play the terrain in your favor by avoiding slopes with exposure to terrain traps that increase the consequences of getting caught in an avalanche. This includes things like cliffs, trees, rocks, and gullies. This layer is becoming more difficult to trigger, but it is still worth considering today.

Unstable test result on the 4/1 interface on a s-facing slope at around 2000′ in the Squirrel Flats area. 04.05.2022