Avalanche Forecast

Fair - Due to the number and quality of field observations

The last of the Pacific fronts should be gone by mid day today, to be replaced by cold clear weather. Cold weather in the forecast for early next week.Friday night: Freezing at valley bottom, no precipitation in the forecast. Cool dry air moves into the region, ridge top winds, NW up to 40Km/h.Saturday: Freezing level at valley bottom no precipitation, sunny, ridge top winds from the north up to 20 Km/h.Sunday: Freezing level at valley bottom, Cold clear weather, ridge top winds around 15-20 Km/h.Monday: Freezing level at valley bottom, Cold clear weather, ridge top winds around 15-20 Km/h., possibility of a temperature inversion in the Alpine.

A skier controlled size 2 avalanched was reported from The Silvern Lake trail yesterday, 30 slope SE aspect, 35cm fracture line, and we are still hearing reports of whumpfing and wind loaded slopes cracking. Numerous skier remote (up to 50 m away) have been reported in the northern part of the region. I would be highly suspicious of wind loaded slopes at all elevations. Use conservative terrain choices and make observations as you travel. Pay attention to solar radiation.

The region has received between 35-90 cm of new snow, with more snow to the western part of the region, tapering of as you travel further east, now overlying a variety of old surfaces. These buried surfaces consist of weak surface facets, surface hoar (more predominant at tree line and below tree line elevations), a scoured crust, wind pressed snow, or any combination of these left over from earlier weather. Whumpfing, cracking, and reports from the field indicate a very poor bond between the new snow and these old surfaces. Reports from the Hankin area on a NE facing slope 1300m show an ice crust down 50cm with facets above and below. A compression test easy @ 25cm and another down @48cm, sudden collapse ( Thanks BH!) Strong winds and slight warming have added cohesion to the storm slab, and transported some of the new snow into deeper, and more destructive wind slabs on the lee side of ridge tops.The mid and lower snowpack are generally strong and well-settled. Basal facets and depth hoar are likely to exist in some parts of the region, but skier triggering has become unlikely. A wind slab avalanche could step down to these basal facets and produce a large destructive avalanche.