Avalanche Forecast

Low - Uncertainty is due to rapidly fluctuating freezing levels. Uncertainty is due to how the snowpack will react to the forecast weather.

THURSDAY NIGHT: Freezing levels fall from 2500 m to around 1200 m by morning. Precipitation begins as rain and transitions to snow. 30-40 mm is forecast with strong to extreme southwest winds. 

FRIDAY: Mostly cloudy with continued snowfall 10-15 cm. Freezing levels remain around 1200 m. Moderate westerly winds. 

SATURDAY: Mostly cloudy with flurries of up to 5 cm. Freezing levels around 800 m. Moderate westerly winds.

SUNDAY: Clearing skies with scattered flurries possible. Freezing levels remain below 1000 m. Light westerly winds. 

High freezing levels and a mix of rain and snow overnight are expected to produce a natural avalanche cycle.

On Wednesday, several natural and rider triggered storm slab avalanches were reported on all aspects to size 2. Previous natural activity from the storm was observed to size 3. Several cornice falls were also reported, some triggered slab avalanches on the slope below. Most avalanches have failed on the buried crust from late March. 

On Tuesday, rider, natural and explosive triggered avalanches were reported to size 2.5. Small avalanches were also remotely triggered, indicating the sensitivity of the recent storm snow. 

Up to 40 mm of precipitation overnight with falling freezing levels will create a mixed bag of conditions on Friday, as snow continues to accumulate.

High elevations can expect up to 40 cm of fresh wind affected storm snow, that will likely be redistributed into deeper deposits on north and east facing slopes over a crust or moist snow. Another widespread and supportive crust is buried 60-100 cm deep, below recent settling storm snow. This crust has recently been very reactive to human and natural triggers. 

Snow will transition to mixed precipitation and rain as elevation decreases. The lowest elevations will likely hold wet surface snow or a crust from heavy overnight rainfall. 

The middle and lower snowpack are generally strong and well bonded. 

• As the storm slab problem gets trickier, the easy solution is to choose more conservative terrain.
• Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
• Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
• Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.