Avalanche Forecast

Moderate - Track of incoming weather systems is uncertain

Monday: 10-20 cm snow Sunday overnight into Monday and another 10-15 cm snow during the day. Moderate to strong south-westerly winds. Alpine temperature warming to near -3. Freezing level rising to 1500m by late afternoon.Tuesday: Light snow (5cm possible). Light to moderate southerly winds. Alpine temperature -4. Wednesday: Cloudy with isolated flurries. Light westerly winds. Alpine temperature near -5.More information can be found in the Mountain Weather Forecast.

Widespread recent avalanche activity was reported on Saturday near Allen Creek. Avalanches from Size 1 to 3 (many triggered by humans) were observed, especially on north east aspects between 1900m and 2600m. See this great MIN report for more information. A widespread natural avalanche cycle is expected with Monday's storm, with the potential for some surprisingly large avalanches given how many persistent weak layers exist in the snowpack.

The current snowpack is complex, with three active weak layers that professionals are monitoring. Recent storm snow has been blown around by winds to form wind slabs and cornices.1) Down about 30-70 cm is a crust and/or surface hoar layer buried mid-January. The surface hoar is up to 10 mm in size, found at all elevation bands and very reactive on north east aspects between 1900-2600m.2) Deeper in the snowpack, the early-January persistent weak layer is found 40 to 120 cm below the surface. It is composed of surface hoar on sheltered slopes and sun crust on steep solar aspects and found at all elevation bands. Snowpack tests show sudden fracture characters with easy to moderate loads and high propagation potential. 3) Another weak layer buried mid-December consisting of a facet/surface hoar/crust combination is buried 100 to 160 cm deep. It is most problematic at and below tree line.A rain crust buried in November is 100 to 200 cm deep and is likely dormant for the time being.See here for a good summary of snowpack test results.