Turnagain Pass

Wind slab avalanches will be the most concerning avalanche problem today. With storm totals upwards of 15-18″ these are expected to be 1-2+’ deep, soft and potentially quite sensitive to human triggers. They are most likely to be found on slopes over 35 degrees just off ridgelines, on rollovers and the side-walls of gullies. Keep an eye out for any slope with signs of recent wind loading – this means areas with stiffer snow over weaker snow, smooth rounded surfaces and hollow feeling snow.

Though the wind died down in most locations yesterday afternoon, it was blowing moderately to strong from the east early in the day yesterday. Though any natural activity has likely ceased, I’m expecting there are some good sized wind slabs that are still fresh enough to cause problems for people. If the visibility breaks enough for travel to the more exposed terrain, finding a 2’ deep unmanageable wind slab is not out of the question.

Below is a poor image of a few small wind slab avalanches on Tincan yesterday (human triggered 2,500′, W aspect). It is still uncertain how the upper elevation wind affected slopes are handling this new load. More on yesterday HERE and HERE.

How is the early December crust behaving?
The new snow did fall on a ~¼” breakable crust which had, in places, surface hoar on top. Though this interface was showing a fairly good bond yesterday, I would not count out that avalanches could be larger and run further with this crust providing a slippery bed surface and the added uncertainty of the now buried surface hoar.

It will be mostly a sluff management day. With decreasing temperature and generally calm to light winds, much of the new snow will be in a very loose unconsolidated state (‘cold smoke’?) and initiating a loose snow avalanche will be likely. In continuously steep, channeled terrain expect sluffs to gain in volume, run fairly far and become more of a concern.