Avalanche Forecast

High -

THURSDAY NIGHT - Cloudy with clear periods and isolated flurries 2-4 cm / south winds 20-40 km/h / alpine low temperature near -14FRIDAY - Cloudy with scattered flurries, 3-5 cm / south winds 15-30 km/h / alpine high temperature near -12SATURDAY - Sunny with cloudy periods / northeast winds 10-15 km/h / alpine high temperature near -14SUNDAY - Mainly sunny / northeast winds, 10-15 km/h / alpine high temperature near -16

On Wednesday, there were reports of several human triggered size 1 wind slab avalanches. Check out this MIN report from Wednesday.There were no avalanches reported Sunday through Tuesday.On Saturday, a persistent slab avalanche was triggered by a skier on a north aspect on a 30 degree slope. Check out the MIN report here. These sorts of avalanches are becoming less frequent, but they are still possible and the consequences are high.There was also evidence of large avalanches (up to size 3) that were triggered by strong wind in the north of the region on Saturday.Last Friday, two small to large (size 1 to 2) persistent slab avalanches were triggered by humans. They were 50 to 70 cm deep and released on the mid-January surface hoar layer described in the Snowpack Summary. They occurred at treeline and alpine elevations on north to northwest aspects.

5-10 cm of snow is expected to fall overnight Thursday and throughout the day on Friday with moderate south winds. Fresh wind slabs are expected to form in lee terrain.Depending on location, the new snow will land on a wide variety of surfaces including 10-30 cm of older low density snow, wind slabs, and sun crusts on south facing slopes.  Winds have been from a variety of directions, so wind slabs may be found on all aspects, mainly in the alpine and at treeline. The older wind slabs will become more difficult to detect as they get buried.A weak layer that was buried in mid January is now buried anywhere from 30-60 cm. This layer consists of surface hoar (feathery crystals) and facets (sugary snow). The layer also likely consists of a crust on south facing slopes. Avalanche activity on this layer has slowed, but test results still indicate that this layer may still be easy for humans to trigger in certain locations. It has been most reactive at treeline and below treeline.The lower snowpack is considered generally strong.