Avalanche Forecast

Issued: Feb 18th, 2021 4:00PM

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

Garth Lemke,

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The Tonquin Area is officially open for winter travel. Use caution as this area is typically more shallow and therefore a weaker snowpack. Otherwise, be vigilant in all terrain for shallow locations being potential human trigger spots.

Summary

Weather Forecast

Friday is expected to be sun and flurries, a trace of new snow, -9C, and Light gusting moderate SW winds. Saturday will be unsettled weather, only a trace of snow, -11 C, and light gusting strong SW winds. There may be a shift in the weather on Sunday with 18cm of snow and strong winds by the end of the day.

Snowpack Summary

Alpine winds continue to create wind slabs in high alpine lee features particularly where local terrain increases the wind action. The upper snowpack are facets and mixed forms over a supportive mid-pack. Thinner snowpack areas it is weak, un-supportive, and facetted.

Avalanche Summary

Thursday's patrol into Whistler creek did not note any new activity. Wednesday's patrol was cut short due to a rescue.

Confidence

Forecast snowfall amounts are uncertain on Sunday

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate to strong SW winds in the alpine and higher RH values are likely creating wind slabs.

  • Travel on ridgetops to avoid wind slabs on slopes below.
  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Caution in thin snowpack areas where triggering is more likely. This is a low probability but high consequence problem.

  • Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1.5 - 3

Valid until: Feb 19th, 2021 4:00PM