Turnagain Pass

There were no known avalanches yesterday. The last avalanches were small wind slabs triggered on Saturday.

A quick hitting storm moved up Cook Inlet yesterday evening hitting Anchorage and Hatcher Pass, but just skirting our forecast region. From Girdwood through Turnagain Pass and into the interior Kenai snowfall totals look to be in the 3-6″ range with some upper elevation zones possibly seeing up to 8″. Ridgetop winds were generally easterly with the snowfall in the 20-25mph range with gusts in the 40’s. As of early this morning, the snowfall and winds have tapered off. A break in storms today may allow the sun to make a brief appearance before the next round of snow hits early tomorrow morning.

The main avalanche concern for today will be fresh new wind slabs that formed last night along ridgelines, on the steep portions of mid-slope rollovers and in cross-loaded gullies. These will most likely be in the Alpine where the winds were the strongest, but could also be found in exposed areas in the trees. Wind slabs should be generally easy to see, soft and on the smaller side due to the meager new snow amounts. The larger ones could be a foot or two deep where the winds were strongest at the high elevations. Watch for the usual signs: surface clues (smooth rounded areas where winds have deposited snow), feeling for stiffer snow over softer snow, and watching for cracks that shoot out from you.

On slopes out of the wind at the mid and upper elevations, watch for easy to trigger dry snow sluffs. Additionally, temperatures should be warming today along with a chance the sun could poke through. On southerly aspects and at the lower elevations, we could see roller balls and possibly some shallow wet/moist sluffs. These could occur both naturally as well as be triggered by people.

We are continuing to track the snowpack as a whole and the various layers of buried crusts that, in places, have weak snow associated with them. As we’ve been mentioning, shallow snowpack zones are the most concerning and where we are finding these weak layers. These areas are on the far north and south of our forecast zone and extend into the interior Kenai. This includes the Summit Lake area (just to the south of our forecast zone) where both natural and human-triggered avalanches failed on old buried weak layers during the strong winds during the middle of last week.

The photo below is of a snowpit on the south end of our forecast zone near Johnson Pass. We are hunting down where the snowpack goes from fairly stable (thicker pack) to unstable (thinner pack). This pit was more indicative of Turnagain Pass with a thicker snow depth and we could not get any layers to fail. However, at the higher elevations where the winds have stripped the snow over the season, thin unstable slopes could exist. Keep this distribution in mind, especially if you are planning on getting out in the zones that have a thinner snow pack. These layers could be quite stubborn to trigger, but the potential is still there for a large avalanche.

Snowpack on the south end of our forecast zone near Johnson Pass at 2,300′.