Avalanche Forecast

Archived

Apr 21st, 2023–Apr 22nd, 2023

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Regions

Little Yoho.

Watch locally for wind slabs in alpine terrain.

Confidence

Moderate

Avalanche Summary

A few small natural loose dry avalanches were noted along the highway corridor Friday. No new slab avalanches were observed or reported today.

Snowpack Summary

A new surface crust has formed on solar aspects to ridge crest. On northerly aspects, up to 40cm of recent storm snow remains preserved. Recent strong winds have created wind-slabs in the alpine. The basal depth hoar is only a concern in shallow snowpack areas. Lower elevations have a temperature crust on all aspects.

Weather Summary

A trough of low pressure will form over the forecast region bringing cloud cover and light precip. A mix of snow and rain will fall at the valley bottom as freezing levels climb to 2200 through the day. Minimal accumulation is expected over higher terrain. Winds will remain in the light to moderate range in the alpine.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.