Since the pre-existing snow is fairly settled and was densified by the very warm temperatures this past week, most of the avalanche problems Friday through the weekend will likely stay within the new snow. We're expecting about 6-10 inches of new snow by midnight on Thursday and it seems to be bonding to the pre-existing snow fairly well, at least when I left around 3 pm but as the snow piles up they should start getting more sensitive. The snow precipitation intensity was quite high at times, so that always makes some density inversions and some sluffing and soft slabs within the new snow. Resorts were reporting sluffs and soft slabs by the end of the day but they seemed fairly soft and manageable. Some sluffs were running fast and far. This snow will likely not change the avalanche danger ratings very much but the next phase of the storm definitely will....

The main portion of the storm should arrive Friday night into Saturday combined with high wind. The main avalanche activity should occur then with sensitive storm snow and wind slabs at many elevations. It appears that the wind will get into lower elevation terrain as well. Total snow by mid day Saturday could approach 2 feet in favored locations, which will certainly push our danger ratings up to Considerable or higher.

Since this form only allows two avalanche problems, I should mention a third problem of wet avalanches. It started out raining hard below about 7,000' and all the pre-existing snow I checked near the road was all isothermal and wet throughout. Since it had already been subjected to strong melting by the very warm temperatures this past week, the rain probably did not effect it very much. Plus, there is very little snow below 7,000' except on the north facing slopes. With the expected colder temperatures overnight, wet avalanches should not be much of a player, but deserve mention.

Although I think most of the deep slab avalanche problems have settled out in the central Wasatch, with an added couple inches of water weight, especially combined with wind, we always have to be suspicious that the added weight will reactivate the deeper weak layers of faceted snow that was so active in the big storms during the first couple weeks of February. If these do get reactivated, they would most likely occur in the thinner snowpack areas outside the Cottonwood Canyon (or on the periphery) or in repeater avalanche paths that slid during the last big avalanche cycle in the first couple weeks of February.

The added weight will almost certainly reactivate deeper weak layers in places like the Uinta Mountains where the snowpack is always weaker and more unstable and avalanche activity has not really ended completely from the last storm.