Summit & Central Kenai Mtns

Recent Avalanches: Several natural avalanches were observed, and one human triggered avalanche was reported in the last week. On March 4 a snowboarder triggered a small avalanche on a north facing slope at about 2,400′ on Manitoba, read the full observation here. The snowboarder was able to ride off the slab without incident. We extend a big thanks to this group for sharing this information as it helps us all understand where this problem exists and how sensitive it is to trigger. The weak layer was likely facets above the President’s Day crust. On Thursday, March 7 we observed a large avalanche on the west face of Templeton Mountain that we believe occurred in the past few days. It’s possible this avalanche failed on a deeper layer of weak snow; the crown looked to be a few feet deep in places. On Thursday, March 7 we noticed some new wet loose avalanches on the south facing slopes of Gilpatrick Mountain.

Weather Recap: It’s been a fairly benign week of weather for a change. Last weekend was cold with nighttime temperatures dipping well below zero F. It has since warmed up with temperatures at the road level climbing above freezing during the day. A mid-week storm brought 2″ of new snow to the Summit Creek weather station over the course of 2 days accompanied by northeast ridgetop winds averaging 19 mph and gusting in the upper 30’s mph. Winds calmed as of Wednesday, March 6 and remain mostly light and variable as of Friday, March 8.

Weather Forecast: This weekend will be one to watch out for changing weather. The forecast is calling for a system to move in Saturday, but the models disagree on timing and snowfall totals. Temperatures look to be in the low teens F Friday night climbing to the mid-20’s F on Saturday. Saturday should start out partly sunny with increasing clouds throughout the day and some light snow beginning as early as the afternoon, but maybe not until the evening hours. Ridgetop winds should remain mostly calm until Sunday morning when they should pick up to 10 to 15 mph gusting into the 20’s mph. Temperatures look to climb to the upper 20’s F on Sunday and light snow should continue to fall through the day to sea level bringing anywhere from 1-8″ of new snow depending on the path of the storm. Active weather is forecast to continue through the week.

Large avalanche that occurred on Templeton Mountain at some point in the last few days. Photo 3.7.2024

There are several different weak layers buried in the Summit Pass snowpack located at different elevations and aspects. There is a chance a person could trigger an avalanche on one of these layers that could be 1-3′ deep and large enough to bury you.

The January facets are still a concern above about 2,400′ where the President’s Day crust is thin or does not exist. See my observation from Tenderfoot on Thursday, March 7 for more on this. These facets are located 1.5′ to 3′ below the surface. They are gaining strength but are still weak enough to cause an avalanche in places. The President’s Day crust is located 6-12″ below the surface and exists from road level up to about 2,500′. This crust now has weak snow above and below. There are also some near surface facets below a slab (about 6″ below the surface) that were found on a north facing slope at 2,600′ on Raven’s Ridge. The best way to assess for this problem is to dig a snowpit in a safe and representative location for where you intend to ski. Stable results don’t necessarily mean you won’t trigger an avalanche as this type of problem has a reputation for being tricky to assess and causing “surprise” avalanches. We can completely avoid this problem by sticking to slopes less than 30 degrees. If you are getting into terrain steeper than 30 degrees we recommend safe travel protocols including traveling one at a time, watching your partner, and moving safe spot to safe spot.

While we don’t expect winds to be a concern on Saturday, ridgetop southeast winds are forecast to pick up on Sunday morning to the 10-15 mph range gusting into the 20’s mph. With the snow that exists on the surface and a few inches of new snow in the forecast we can expect these winds will be forming fresh wind slabs up to 1′ deep. These slabs will be more likely and more sensitive in the upper elevations. Watch for blowing snow off ridgelines and across gully features. Wind slabs can be fairly soft especially with these wind speeds, but they should still feel like firm snow over soft snow if you stick your probe or pole in the snow. You can ride or jump on a small test slope to see how sensitive a new wind slab is to your weight. A shooting crack or a whumpf is a sign that the snowpack needs time to adjust to the new load.

Wet Loose: This weekend looks to be mostly cloudy, but if the sun comes out at any point it doesn’t take much time for the snow to heat up on slopes facing the sun and cause a wet loose avalanche also known as a “sluff.” These slides are usually triggered next to rocks and alders that are collecting heat. If we are caught in one of these slides, they are difficult to manage because of the weight of the wet snow. Look for colder snow on a different aspect if you see “roller balls” (sometimes a pre-curser to wet loose) or wet loose slides occurring.

A shooting crack like this one I found last week on Raven’s Ridge is a clear sign that the slab needs time to bond to the snow beneath. Photo 2.28.2024

Wet loose avalanches on the south facing slopes of Gilpatrick Mountain. 2.7.2024