Avalanche Forecast

Archived

Apr 13th, 2025–Apr 14th, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Regions

Yukon, Tutshi, Wheaton, White Pass East, White Pass West, Haines Pass.

Exercise caution when moving into wind-loaded terrain.

Recent snowfall and strong winds have formed wind slabs in lee features.

Confidence

Moderate

Avalanche Summary

On Friday, a report outlined a human triggered large (size 2) wind slab avalanche. Location was unspecified , but in the western reaches of the forecast region.

Additionally a report from the east side of the white pass, indicated that a machine trigger a large (size 2) wind slab avalanche on a steep north aspect feature at 1200 m.

If you observe an avalanche, please share your observations on the Mountain Information Network.

Snowpack Summary

Recent strong southerly winds have distributed recent snow onto north aspects, creating reactive wind slabs. 15-25 cm of settled surface snow can be found in sheltered areas and a melt-freeze crust covers most solar slopes as well as northerly slopes up to 1250 m.

Below 1100 m the snowpack is wet and unconsolidated.

A buried surface hoar or crust layer, 40 to 60 cm deep, is variable in distribution.
A December crust with facets, 100 to 150 cm deep on all aspects up to 1750 m, has shown no significant test results.

Snow depth ranges from 100 cm at highway elevations to over 300 cm in the alpine.

Weather Summary

Sunday Night

Cloudy with up to 10 cm of snow. 50 to 70 km/h south ridgetop wind. Treeline temperature -3 °C.

Monday

Mostly cloudy with 0 to 3 cm of snow. 40 to 70 km/h south ridgetop wind. Treeline temperature -6 °C.

Tuesday

Mostly cloudy with 5 to 10 cm of snow. 40 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 900 m.

Wednesday

Mostly cloudy with up to 5 cm of snow. 40 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 900 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.