Avalanche Forecast
Issued: Apr 11th, 2017 3:54PM
The alpine rating is Cornices and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Low - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
There's significant uncertainty surrounding precipitation on Wednesday-Thursday (wide range given), and then some clearing for Friday. WEDNESDAY: Flurries late morning into the afternoon (5-10cm). Moderate southerly ridgetop winds. Freezing level around 1700 m.THURSDAY: Snow continues Wednesday overnight with 5-20cm possible by Thursday afternoon. Moderate southwest ridgetop winds. Freezing level around 1900 m.FRIDAY: Clearing Thursday overnight and then cloudy by Friday afternoon. Strong southwest ridgetop winds. Freezing level around 1800 m.
Avalanche Summary
On Tuesday, skiers were able to trigger a 20cm deep Size 1.5 wind slab on an east aspect near Fernie. On Monday, several storm slabs and cornice triggered slabs to Size 2.0 were reported on northerly aspects between 1750m and 2100m.Some small, loose wet avalanches to Size 1.5 were reported on south facing aspects near 1750m in the afternoon on Monday.
Snowpack Summary
Since Saturday morning, 15-30 cm of new snow has fallen at treeline and above. The sun on Monday & Tuesday made snow surfaces moist and unstable during the day, but it should stabilize quickly after an overnight refreeze. This new snow sits on a very hard crust up to 1400m (on north aspects) and up to 1700m (on south aspects).Moderate southwesterly winds have created wind slabs on lee features below alpine ridgetops. Cornices are large, looming, and best avoided.The snowpack is generally well settled and continues to transition into a spring snowpack, becoming isothermal at treeline in some areas and below treeline in most areas.The December facets and November rain crust are buried deep, but these deep persistent weaknesses have not been reactive for several weeks. That said, rapid warming of the snowpack or a large trigger, like a cornice, could trigger this layer.
Problems
Cornices
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood
Expected Size
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 12th, 2017 2:00PM