Archived

Avalanche Forecast

Apr 13th, 2018–Apr 14th, 2018

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Kootenay Boundary.

Steady precipitation over the coming days will gradually elevate the avalanche danger. There is uncertainty for the amount and type (snow or rain) and also for the freezing level during the period.

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

SATURDAY: Mix of sun and cloud with flurries, accumulation 5-10cm mostly overnight Friday into Saturday / Light to moderate southwest wind / Alpine temperature 0 / Freezing level 1800m SUNDAY:Â Cloudy with wet flurries, accumulation 5-10cm / Light southwest wind / Alpine temperature 3 / Freezing level 2100m MONDAY: Periods of snow or rain, accumulation 10-20cm / Light west wind / Alpine temperature 0 / Freezing level 1700m

Avalanche Summary

On Thursday and Friday, reports indicated loose dry and wet avalanche activity from steep slopes and terrain features at tree line to size 1.5. No new avalanche observations reported on Wednesday.

Snowpack Summary

20-30cm of moist new snow is sitting on previous moist snow or crust surfaces . Recent winds from the southeast and southwest have sifted the new snow, forming isolated wind slabs in leeward terrain features and slopes. With freezing levels rising, surface snow will likely become moist through the day. The mid and lower snowpack is generally well-settled and strong.

Avalanche Problems

Storm Slabs

Building storm slabs will likely be reactive to human triggers, especially as the snow totals accumulate through the forecast period. Isolated pockets of wind slab may exist behind ridge lines.

Watch for signs of instability such as whumpfing, cracking, or moist/ wet surface snow.Observe for the bond of new snow with the old surface before committing into avalanche terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Loose Wet

Warm temperatures and/or rain at lower elevations will weaken the surface snow and cause it to sluff in steep terrain.

Use caution above cliffs and terrain traps where small avalanches may have severe consequences.Avoid steep slopes when air temperatures are warm or the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 1.5