Avalanche Forecast

Unsettled conditions will exist on Thursday as the cold front weakens and a new low develops near Haida Gwaii.

Overnight Wednesday: Snow amounts 10-20 cm with strong ridgetop wind from the southwest. Alpine temperatures near -7 and freezing levels valley bottom.

Thursday: Snow 10-20 cm. Ridgetop wind generally light with gusty periods from the southwest. Alpine temperatures near -4 and freezing levels 600 m.

Friday: Snow amounts 5-15 cm. Ridgetop wind strong from the South and freezing levels 600 m.

Saturday: A mix of sun and cloud. Ridgetop wind light from the southwest and freezing levels 700 m.

By Wednesday afternoon a glide slab avalanche size 1.5 was reported from a 35-degree rocky slope at 500 m. Avalanche activity is expected to increase on Thursday with new snow and strong southwest wind. 

Storm snow amounts will continue to accumulate overnight Wednesday building reactive storm slabs by Thursday. 

The recent snow adds to the 30-60 cm that fell at upper elevations last weekend. Much of the recent precipitation fell as rain at lower elevations and the snow surface below treeline is a melt-freeze crust in many areas.  

At higher elevations, the new snow has added significant load to a couple of deeply buried weak layers. The first persistent weak layer was buried in mid-March and is around 100-180 cm deep. It consists of surface hoar on sheltered northerly aspects around treeline and down between 150 to 250 cm is another layer of surface hoar and facets, buried in mid-February. At this time, these layers linger in the snowpack but haven't recently been a reactive avalanche problem. 

The mid and lower snowpack is well settled and strong in most areas.

• Watch for fresh storm slabs building throughout the day.
• Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
• Start with conservative lines and watch for clues of instability.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.