Avalanche Forecast

Issued: Apr 10th, 2017 3:57PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs and Loose Wet.

istorm, Avalanche Canada

South Coast.

It's still winter at higher elevations.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TUESDAY: Mix of sun & cloud. No new precipitation but there could be as much as 15 or 20 cm from the previous storm at the highest elevations. Warmer with alpine temperatures up to +6 C and freezing level near 1600m. Light east wind.WEDNESDAY: Overcast sky. Rain, up to 20 mm at most elevations but mixed with snow at higher locales. Freezing level around 1600m Moderate winds with strong gusts from the east.THURSDAY: Overcast sky. Rain or snow depending on elevation, new snow amounts 5 - 15 cm. Freezing level around 1200m with alpine temperatures around zero or slightly above. Light to moderate Southerly winds.

Avalanche Summary

On Tuesday, the main concern will be isolated wind slab avalanches near the peaks where the recent precipitation fell as snow and was drifted by the wind. At tree line expect small loose wet avalanches in steep terrain if the sun appears for any length of time. Saturday's fatal avalanche on Mt Harvey (near Lion's Bay) was the result of people being on a cornice that failed. A large avalanche was subsequently triggered by the multi-ton snow boulders hitting the slope below.

Snowpack Summary

Saturday's cold stormy weather brought snow to the mountains as low as 800m. Temperatures have warmed slightly but freezing level near 1200m Sunday and Monday means it's still winter up high! Anywhere from 5 to 15 cm of snow fell within the region on Sunday & Monday. With mostly light winds there may be pockets of isolated wind slabs at higher elevations. The depth of recent new snow taper with elevation. At lower elevations, rain has saturated an already wet snowpack.

Problems

Wind Slabs

Warm temperatures and limited wind should help recent snow bond and settle in place; however, isolated wind slabs may linger.

Use caution in lee areas. Recent wind loading has created wind slabs.Be cautious as you transition into wind affected terrain.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Loose Wet

Rain at lower elevations has led to a gradual break down of surface crusts and has contributed to wet snow sluffing and gathering mass in steep terrain. Forecast sunshine on Tuesday could shift the problem to higher elevations.

Use caution above cliffs and terrain traps where small avalanches may have severe consequences.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Apr 11th, 2017 2:00PM