Avalanche danger will increase through the day as new snow and wind form touchy storm slabs. Stick to simple, wind-sheltered terrain.
Touchy slabs are likely forming at elevations above 1500 m. Their size and likelihood will increase throughout the day as 15-30 cm of snow is expected with strong southwest wind. Natural avalanches will be very likely in the alpine and on steep wind loaded slopes at treeline.
Saturday night: 5-15 cm new snow, 40-50 km/h southwest wind. Freezing level 1500 m. Alpine temperature -5.
Sunday: 10-20 cm new snow. 50-70 km/h southwest wind. Freezing level up to 1500 m. Alpine temperature -5.
Monday: Flurries. 30 km/h northwest wind. Freezing level drops to valley bottom. Alpine temperature -13
Tuesday: Mix of sun and cloud. 20 km/h northwest wind. Freezing level 1400 m. Alpine temperature -8.
Recent avalanche activity has primarily been small (size 1-1.5) wind slab and dry loose avalanches in the top 20 cm of snow. A few larger slab 2 avalanches have been observed in steep slide paths in Glacier NP over the past few days. One notable size 3 slab avalanche was observed northeast of Revelstoke on Wednesday. The avalanche failed on the ground on a south aspect at 1600 m. While an isolated event, it is a good reminder to watch for slopes warming up in the springtime heat.
With 5-20 cm forecast per 12 hour period, by Sunday afternoon you could see 20 to 40 cm of fresh snow. Accompanied by strong wind, this new snow will likely form touchy slabs.
50-100 cm now sits above an interface that formed during the mid-March dry spell, which consists of a widespread crust (except on north-facing slopes above 1800 m). Overall the snow seems to be bonding well to this interface, although there have been some isolated human triggered avalanches running on the crust layer over the past few days.
Lower elevations have undergone daily melt-freeze cycles, with moist or crusty surfaces likely found up to at least 1600 m.
