Avalanche Forecast

Issued: Mar 15th, 2018 4:53PM

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

Avalanche Canada cgarritty, Avalanche Canada

Lingering wind slabs remain a concern in the north of the region. Exercise increasing caution around solar aspects and lower elevations as loose wet avalanche conditions develop over the day.

Summary

Confidence

High -

Weather Forecast

Friday: A mix of sun and cloud, clearer in the north. Light north or variable winds. Freezing level to 1500 metres with alpine high temperatures around -4, slightly warmer in the south of the region.Saturday: Mainly cloudy with isolated flurries and a trace of new snow, increasing overnight. Light north winds. Freezing level to 1400 metres with alpine high temperatures of -5, slightly warmer in the south of the region.Sunday: Continuing light flurries with up to 5 cm of accumulated new snow by end of day. Light to moderate northwest winds. Freezing level to 1400 metres with alpine high temperatures around -5, slightly warmer in the south of the region.

Avalanche Summary

A report from Monday showed one size 1.5 wind slab that released with skier traffic on a steeper north aspect (near ridgecrest) in the alpine near Birkenhead Lake. Several solar triggered loose wet releases were reported, averaging size 1.5-2 but reaching size 3 in isolated areas.Reports from Sunday show primarily solar induced avalanches size 1.5-2 on south and west facing sun exposed slopes during the heat of the day. On Saturday a skier triggered size 2 wind slab avalanche was reported from the north of the region on a northeast aspect in the alpine. There was also a report of natural size 2 wind slab avalanche on a northwest aspect in the alpine. Avalanche activity on Friday was reported as either loose dry to size 1 or wind slab activity to size 1-1.5 on northerly aspects at tree line.

Snowpack Summary

5-10 cm of new snow accumulated on Wednesday. In most areas, the new snow has buried a breakable crust formed after days of warm temperatures and sunshine. On higher elevation north aspects in the north of the region, is overlies a mix of about 20 cm of either low density or wind-redistributed storm snow from last week. This older storm snow sits on a sun crust on steep south-facing slopes, cold dry snow and possibly small surface hoar on shady aspects.In the north of the region a weak layer buried in mid-February is about 40-50 cm below the surface and has been reactive in some snowpack tests. The layer is composed of sugary facets, a sun crust on solar aspects, and surface hoar that is present at and below treeline. The snowpack is well settled in the south of the region around the Coquihalla and in Manning Park.Variable winds in the past month have created cornices on many alpine ridgelines. They become touchier as daily temperatures rise and with the strong late winter sun on clear days.

Problems

Wind Slabs

An icon showing Wind Slabs
Recent snowfall and southerly winds formed wind slabs in the lee of exposed terrain at higher elevations. South aspects aren't exempt - they become an increasing concern over the day as sun and warming set up loose wet avalanche conditions.
Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Use ridges or ribs to avoid pockets of wind loaded snow.Extra caution needed around cornices with current conditions.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 16th, 2018 2:00PM