Avalanche Forecast

Archived

Apr 21st, 2025–Apr 23rd, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Cool daytime temps and limited solar should make for some great spring touring this week!

Start and end your day early!

Confidence

Moderate

Avalanche Summary

Large cornice failures and wind slabs have been observed at alpine elevations.

Wednesday

Large cornice failures and wind slabs have been observed at alpine elevations.

Snowpack Summary

In many sheltered areas, 5-20 cm of soft pow-pow exists. Recent variable loading has wind slabs building on all aspects in the alpine.

The snowpack at treeline and below is a series of crusts and moist snow. Easy travel requires good timing and an overnight freeze to get to the good stuff. The lower snowpack is dry, faceted, and weak.

High north aspects offer the best spring riding conditions, though the snowpack remains susceptible to triggering deeper, unstable layers.

Weather Summary

Overnight: Clear periods. Low -9 °C. Light winds to 25 km/h.

Tuesday: A mix of sun and cloud. High: -4 °C. Ridge wind light to 20 km/h. Freezing level: 1800 metres.

Wednesday: A mix of sun/clouds with isolated flurries. Temps: Low -7 °C, High -1 °C. Ridge wind light to 20 km/h. Freezing level: 2100 metres.

Thursday: Sunny.

Friday: Sunny

Terrain and Travel Advice

Pay attention to cornices and give them a wide berth when traveling on or below ridges.

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.