Avalanche Forecast

Issued: Apr 17th, 2022 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada wlewis, Avalanche Canada

Winter continues with another round of new snow - watch for reactive storm slabs at all elevations. 

Stick to conservative terrain and minimize your exposure during heavy snow or wind.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain. Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack. We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

SUNDAY NIGHT: Mostly cloudy, with snow beginning overnight. 5-20 cm is expected by morning. Strong south/south easterly winds. Freezing levels fall to 500 m. 

MONDAY: Snow continues with 10-30 cm expected, favouring western terrain, freezing levels reach 1300 m. Strong southeast winds ease over the day. 

TUESDAY: Cloudy up to 5 cm of snow over the day. Freezing levels reach 1000 m. Moderate southerly winds. 

WEDNESDAY: Clearing skies with no snowfall expected. Moderate southeast winds. Freezing levels rise to 1300 m.  

Avalanche Summary

No new avalanches have been reported. Periods of strong sunshine in many areas have produced pinwheeling and small point releases this week.

Observations are limited at this time of year, so please consider posting to the Mountain Information Network.

Snowpack Summary

10-55 cm of storm snow is expected by Monday afternoon. This will likely form reactive storm slabs at all elevations above the freezing level. Deeper deposits are expected in west and north facing terrain features at higher elevations, as strong south-southeast winds are forecast. 

Several thin crusts exist on south facing slopes from recent sunshine, and a widespread and supportive crust is now buried 30-80 cm deep. Reports suggest these crusts are currently bonding well with the layers around it. 

The mid and lower snowpack is considered strong at this time, consisting of hard snow and melt freeze crusts. 

Terrain and Travel

  • As the storm slab problem gets trickier, the easy solution is to choose more conservative terrain.
  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Minimize exposure during periods of heavy loading from new snow and wind.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Storm Slabs

An icon showing Storm Slabs

Storm slabs will build over the day as snowfall totals increase. Expect reactivity as storm snow falls on a variety of surfaces including a crust on south facing slopes. Lower elevations may see rain or mixed precipitation. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Apr 18th, 2022 4:00PM