Avalanche Forecast
Issued: Mar 18th, 2017 3:22PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
shorton,
Avalanche Canada
Time to be extra cautious in avalanche terrain. Deep weak layers are under stress and have been producing large avalanches recently.
Summary
Confidence
Moderate -
Weather Forecast
SUNDAY: Sunny, moderate northwest winds, alpine temperatures around -8 C.MONDAY: Mix of sun and cloud, light winds, alpine temperatures around -5 C.TUESDAY: Afternoon flurries with 5-10 cm, light southwest winds, freezing level climbing to 1500 m with alpine temperatures around -2 C.
Avalanche Summary
Initial reports from Saturday include numerous natural and skier triggered loose wet avalanches at lower elevations (size 1.5) . Reports from Friday include several large natural avalanches including a size 3 persistent slab in the Rossland range and up to size 3.5 deep persistent slabs in the Valhallas (failing on basal facets over 2 m deep).The upper snowpack should stabilize with cooler temperatures, but deeper persistent weak layers remain under heavy stress and have the potential for large and surprising avalanches.
Snowpack Summary
Rain has soaked the upper snowpack for a second time in a week. This time all the way to mountain tops. Cooling temperatures will gradually form a rain crust on the surface, but expect a thick layer of moist snow in the upper snowpack for some time. This heavy snow will stress a number of deeper weak layers including the late-February facet / surface hoar interface (70-120 cm deep), the mid-February crust (90-130 cm deep), and basal facets in shallow snowpack areas.
Problems
Persistent Slabs
Deep weak layers are under heavy stress after recent loading and warming, creating the potential for large and surprising avalanches.
Use careful route-finding and stick to moderate slope angles with low consequencesAvoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Be aware of thin areas that may propogate to deeper instabilites.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 19th, 2017 2:00PM
