As of Thursday, the Chugach National Forest Avalanche Information Center had recorded 11 avalanches this week — nine in the Turnagain Pass, one near Summit Lake, and one near Girdwood, which derailed a freight train early Tuesday morning.
Thursday’s avalanche forecast warned of high avalanche danger, and cautioned against traveling in avalanche terrain, especially at elevations above 2,500 feet.
Contributing to the high avalanche danger are strong winds transporting snow and burying what the center calls “weak layers.”
The danger of an avalanche is only likely to increase with more snowfall expected through Friday in the Turnagain Pass and around Seward.
Thursday’s forecast warned especially of the area around Seward and Lost Lake, saying that the area is expected to get significantly more snow than others, up to a foot.
“Avalanche danger will increase rapidly with new snowfall and wind,” the forecast reads.
The center warns those traveling outside to watch for “red flags,” which include a sudden collapse that may be accompanied by an audible “whumpf”; significant quantities of new snow or rainfall; sudden warming of temperatures; cracks; and blowing snow caused by high winds.
Another indicator for avalanche risk is “load rate.” If a lot of snow is moved on top of an existing layer quickly, it may lead to an avalanche.
“We recommend very conservative terrain selection and avoiding avalanche terrain altogether if you say any red flags,” the center writes.
Around the Turnagain Pass and Girdwood, the wind is the biggest issue, according to Thursday’s forecast. Gusts exceeding 50 miles per hour are transporting snow at upper elevations, rapidly loading and burying surface layers. The combination of “a short but intense snow storm followed by strong winds,” creates the possibility for large and deep avalanches, or cascading smaller avalanches that then step down to deeply buried and weaker layers and cause larger avalanches.
For daily avalanche forecasts and more information about avalanches in the Turnagain Pass, visit cnfaic.org.
Reach reporter Jake Dye at jacob.dye@peninsulaclarion.com.
