Avalanche Canada dsaly, Avalanche Canada

South Coast Inland Avalanche Forecast

Apr 23rd, 2019 3:00PM

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.

Wind slabs may react to human triggers around ridges and lee features. Loose wet avalanches remain a concern, especially on sunny slopes.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TUESDAY NIGHT: Mostly cloudy with isolated wet flurries, light west wind, alpine temperature -8 C, freezing level 800 m.

WEDNESDAY: A mix of sun and clouds, light southwest wind, alpine temperature -2 C, freezing level 1800 m.

THURSDAY: Cloudy with sunny periods, light east wind, alpine temperature 0 C, freezing level 2000 m.

FRIDAY: Cloudy with sunny periods, light southwest wind gusting to 40 km/h, alpine temperature 0 C, freezing level 2000 m.

Avalanche Summary

Snowballing and loose wet avalanches to size 1.5 were observed in the Duffey Lake area on Saturday.

There have been few observations in the South Coast Inland Region, however the neighboring Sea to Sky region observed a natural avalanche cycle into Saturday. Loose wet avalanches to size 2, wet slab avalanches to size 3, and large cornices failing naturally and triggering slab avalanches to size 3 on the slopes below were reported around the region.

If you have any recent observations during your travels, we would greatly appreciate it. If you posted a photo or any other information to the Mountain Information Network (MIN), thanks!

Snowpack Summary

In the alpine, up to 10 cm cold wind-affected snow is holding onto northerly aspects. Recent precipitation fell as rain upwards of 1800 m. Southerly winds have produced isolated drifts around ridges and in immediate lee features at upper elevations, cornices have been touchy recently.

A crust is found on solar alpine slopes and all aspects below. Warm overnight temperatures will prevent crust recovery as you lose elevation. Expect thin surface crusts to break down quickly with daytime warming. Below treeline the snowpack is saturated and rapidly melting.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 1.5

South-southwesterly winds have produced isolated pockets of snow around ridges and immediate lees. Cornices may be touchy, give them plenty of space.

  • Cornices may be touchy and could trigger wind slabs on slopes below.
  • Be careful with wind-loaded pockets, especially near ridge crests.
  • Use extra caution on slopes if the snow is moist or wet.

Aspects:

North, North East, East, West, North West.

Elevations:

Alpine, Treeline.

Loose Wet

An icon showing Loose Wet

Likelihood

Possible - Unlikely

Expected Size

1 - 1.5

The likelihood of loose wet avalanches will depend on the extent of overnight crust recovery and the pace at which the warms through the day.

  • Minimize overhead exposure and avoid steep slopes during periods of strong sun.
  • Avoid terrain traps such as cliffs and gullies that increase the consequence of small avalanches.

Aspects:

East, South East, South, South West, West.

Elevations:

Alpine, Treeline.

Valid until: Apr 24th, 2019 2:00PM