Avalanche Forecast

Archived

Mar 21st, 2026–Mar 22nd, 2026

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Below Threshold.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Below Threshold.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Regions

Haines Pass, Chilkat Pass.

Triggering large storm slabs on weak facets is most likely in wind affected terrain.

Use conservative route selection. Choose simple, low angle terrain with no overhead hazard.

Confidence

Low

We are uncertain due to a limited number of field observations.

Avalanche Summary

On Friday, around 30 cm of recent storm snow sitting on a crust/facet layer was reactive to skiers on small test slopes at treeline. See MIN.

Observations in this region are extremely limited. If you head out into the backcountry, let us know what you're seeing by submitting a MIN report.

Snowpack Summary

Cornices are large and looming. Avoid traveling underneath them.

30 to 40 cm of recent snow and strong winds have formed storm slabs over a weak layer of crust/facets that have recently been reactive to human triggers.

There are multiple persistent weak layers of facets or crust/facets combinations in the top 100 cm of the snowpack. These layers are most likely to trigger in wind affected areas with a shallow or thick to thin snowpack.

Weather Summary

Saturday Night
Mostly cloudy. 3 to 10 cm of snow. 40 km/h southeast ridgetop wind. Treeline temperature -8 °C.

Sunday
Mix of sun and clouds. 0 to 3 cm of snow. 30 km/h southeast ridgetop wind. Treeline temperature -9 °C.

Monday
Mix of sun and clouds. 20 km/h east ridgetop wind. Treeline temperature -11 °C.

Tuesday
Mix of sun and clouds. 30 km/h east ridgetop wind. Treeline temperature -11 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Use conservative route selection. Choose simple, low angle terrain with no overhead hazard.
Be aware of the potential for large avalanches due to buried weak layers.
Be especially cautious as you transition into wind-affected terrain.
Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
Cornice failures could trigger large and destructive avalanches.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.