Avalanche Forecast
Issued: Feb 18th, 2019 4:44PM
The alpine rating is Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
High -
Weather Forecast
MONDAY NIGHT - cloudy with clear periods / southwest winds 10-20 km/h / alpine low temperature near -15TUESDAY - Mainly cloudy with flurries, 2-4 cm / southwest winds 10-25 km/h / alpine high temperature near -10WEDNESDAY - A mix of sun and cloud / north winds 10-20 km/h / alpine high temperature near -9THURSDAY - Mainly sunny with cloudy periods / northwest winds, 10-15 km/h / alpine high temperature near -13
Avalanche Summary
On Sunday, several natural and human triggered wind slab avalanches up to size 2 were reported. Several natural loose snow avalanches were reported on steep solar terrain, size 1.5-2.5.On Saturday, skiers triggered a few small (size 1) storm slabs and wind slabs as well as one larger (size 2) persistent slab avalanche. The persistent slab avalanche was triggered on a north aspect at 2100 m and failed on a 60 cm deep surface hoar layer. On Friday, a few size 1.5 persistent slab avalanches were were remotely triggered on north aspects at treeline, failing on 40-60 cm deep surface hoar layers. Some larger (size 2) persistent slab avalanches were triggered on the same layers just outside the region boundary. More persistent slab activity occurred earlier in the week, predominantly on northeast aspects between 1200 and 1900 m.
Snowpack Summary
10-15 cm of low density snow has been blown around by recent strong northerly winds, creating reverse-loading on some slopes. Two prominent weak layers have been responsible for several dangerous avalanches in the past two weeks. The upper layer was buried at the end of January and lies approximately 40 cm below the surface. The deeper one was buried mid-January and lies approximately 75 cm below the surface. Both consists of a mix of surface hoar (feathery crystals) and facets (sugary snow) and may lie on top of a sun crust on southerly aspects. Both layers are potentially reactive and in any given location, one or both could exist in the snowpack. Wide propagation has been noted, meaning avalanches have the potential to be large (up to size 3). These weak layers are most prevalent at treeline and below, but may also be found in sheltered areas in the alpine.Average snow depths are approximately 300 cm. Very sporadically, failures have occurred near the base of the snowpack in this region, or in neighboring regions. These releases have almost all been from high alpine areas, possibly triggered close to rocky features.
Problems
Persistent Slabs
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Wind Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 19th, 2019 2:00PM