Avalanche Forecast

High

Large, naturally triggered persistent slab activity continued on Wednesday with up to size 3 avalanches observed in the past 2 days. Most have been naturally triggered from warming and sun, although some were remote-triggered from 150 to 300 m away indicating a very weak snowpack.

Continued persistent slab activity is expected, as well as widespread loose wet avalanches and cornice failures as warming continues.

Expect to find moist or wet snow at all elevations except the highest north facing terrain. 40 to 80 cm of snow from the past week is rapidly settling over a variety of layers including surface hoar in isolated shady areas.

A weak layer composed of weak faceted grains on a crust is now buried 80 to 150 cm deep. This layer remains sensitive to both human and natural triggers and continues to produce large, destructive avalanches.

The warm temperatures are expected to increase reactivity of all buried weak layers, producing large natural avalanches.

Thursday Night

Mostly clear. 20 km/h northwest ridgetop wind. Freezing levels remain above 3000 m overnight.

Friday

Sunny. 30 km/h north wind. Treeline temperature +6 °C with freezing level climbing to 3300 m.

Saturday

Sunny. 20 km/h southeast ridgetop wind. Treeline temperature +8 °C with freezing level steady at 3300 m.

Sunday

Sunny. 30 km/h southeast ridgetop wind. Treeline temperature +8 °C with freezing level holding at 3300 m.

More details can be found in the Mountain Weather Forecast.

• Avoid avalanche terrain during periods of strong sun.
• Cornice failure may trigger large avalanches.
• Avoid the runout zones of avalanche paths. Very large avalanches have been running full path.
• The likelihood of deep persistent slab avalanches will increase with each day of warm weather.