Avalanche Forecast

Issued: Apr 23rd, 2016 9:06AM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Wet Slabs, Loose Wet and Storm Slabs.

pgoddard, Avalanche Canada

Kootenay Boundary.

Spring conditions. Watch for rain weakening the snowpack.

Summary

Weather Forecast

A cold front arriving overnight and lingering on Sunday brings 10-15 mm precipitation, with moderate to strong SW winds. The freezing level should fall to around 1800 m by Sunday afternoon. A mix of sun and cloud, light winds and mild temperatures are expected on Monday and Tuesday.

Avalanche Summary

Most operators have shut down for the season. Please continue to share your backcountry observations through the Mountain Information Network.

Snowpack Summary

As temperatures gradually cool through the weekend, loose wet and wet slab avalanches will become less likely. Storm slabs may develop in the alpine as the cold front passes through. At lower elevations, monitor the overnight freeze of the snow surface. If the snow surface does not freeze overnight or if the crust is thin or breakable, daytime heating or rain will weaken the snowpack much more quickly than if there is a well frozen thick crust. Low elevation and thin snowpack areas are isothermal.

Problems

Wet Slabs

Wet slabs are becoming less likely, but could still occur during rainfall. Glide slabs may also occur where the whole snowpack is sliding on a smooth ground surface, like rock slabs.

Be aware of the potential for large, deep avalanches. >Avoid slopes with glide cracks. >

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

3 - 6

Loose Wet

Loose wet avalanches may be triggered by rain or sun.

Watch for surface clues such as sluffing off of cliffs and pinwheeling. These are red flags that should prompt you to reevaluate the conditions. >Be cautious of steep terrain if it is warm or raining, especially if the snow is moist or wet. >

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Storm Slabs

Forecast new snow and wind may form storm slabs at upper elevations.

Choose well supported terrain without convexities.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 24th, 2016 2:00PM