The quick change from stormy weather to clear sunny skies with high freezing levels is a concern for natural avalanches. This is not the time for big objectives.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain on Friday
Weather Forecast
Overnight: 5-10 cm of new snow with freezing down to 1300 metres by morning. Friday: Clearing in the morning, with strong solar in the afternoon. Daytime freezing rising up to 2200 metres with light southwest winds. Saturday: Little or no re-freeze below 2200 metres. Mix of sun and cloud with flurries developing in the afternoon. Sunday: Overcast with light snow and light winds. Daytime freezing levels around 1800 metres.
Avalanche Summary
Numerous storm slab and loose wet avalanches were reported from the Fernie area on Thursday. One natural cornice fall was size 3.0, and pulled a storm slab from the slope below. Our uncertainty revolves around whether the snowpack will get a chance to re-freeze in the morning before the sun starts to heat the snowpack. I think there is a good chance that storm slabs will continue to be reactive, and strong solar may release cornices and storm slabs as daytime temperatures and freezing levels climb.
Snowpack Summary
Storm slabs continue to grow at higher elevations. Another 10-15 cm by Thursday morning has made the recent storm total near Fernie 50-70 cm. In the Corbin area, there was a total of 25cm on Wednesday. Storm snow is not bonding well to crusts in the alpine and at treeline. Below 1800 metres the snow is moist or wet. The recent storm snow may be sitting on a crust that developed just before the new snow arrived. This crust may act as a smooth sliding surface when the sun heats the storm slab. Deeply buried facets may spring to life due to the added load of the storm slabs, and the possibility of strong solar radiation over the next couple of days.
triley,
Avalanche Canada
