Avalanche Forecast

Issued: Feb 21st, 2020 1:00AM

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

VIAC Jesse Percival, VIAC

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No new avalanches observed or report.

Summary

Past Weather

Mostly clear sky with some fog and afternoon convective clouds. Overnight temperatures have remained cool, freezing levels nearing sea level. Daytime warming and sun effect caused freezing levels to rise to the 1500-meter mark.

Weather Forecast

A high pressure to the north east of the island has persisted but is forecast to come to an end late Friday. Saturday an expected incoming weather systems will begin to deliver snow and wind, with a subsequent stronger weather system arriving Sunday.Friday: Trace amounts of snow late in the day, Winds Moderate from the South West, Freezing levels to 1000 meters.Saturday: 5 to 10 cm of snow, Winds Strong from the South West, Freezing levels to 1000 meters.Sunday: 15 to 25 cm of snow, Winds Strong from the South West, Freezing levels 1000 meters.

Terrain Advice

Careful route find and snow-pack evaluation are paramount during periods of heavy snowfall and strong winds.Avoid traveling both above and below cornice features.Careful and cautious route finding when entering into or over convex rolls or steep features.

Snowpack Summary

Daytime warming with freezing levels up-to 1500 meters and periods of sun is continuing to settle the snow pack. The surface snow on steep solar aspects has seen the development of a sun crust, Exposed ridge tops are scoured down to the Jan 31 melt freeze crust. Non solar protected areas continue to grow surface hoar and will in the coming storm system become a weakness and concern under the new storm snow. The mid and lower snow-pack is well settled and dense.

Snowpack Details

  • Surface: Variable surfaces conditions from wind loaded to wind pressed and on solar aspects a breakable sun crust. On areas protected from the wind and sun, surface hoar growth is prevalent.
  • Upper: A supportive and reactive melt freeze crust down from 15 to 30 cm.
  • Mid: A variety of old crusts can be found.
  • Lower: well settled and dense

Confidence

Moderate - Limited Alpine Field Observations

Problems

Loose Wet

An icon showing Loose Wet
Daytime warming and the suns effect on surface snow may cause snow to become unconsolidated on south aspects. This avalanche problem when triggered is likely to remain small, but on isolated terrain features that are steep and direct solar, this may promote a small avalanche to gain mass and result in a large, size 2. Expect this avalanche problem to become no existent once the incoming storm obscures the sun and the air temperature cools. **Location:** On all south aspects and found at all elevations. **Possibility:** Triggering of this avalanche problem is possible from light loads such as skiers. Natural avalanches are unlikely. **Size:** If triggered expect these avalanches to be small, and on isolated terrain features large, size 2.

Likelihood

Possible

Expected Size

1 - 1

Wind Slabs

An icon showing Wind Slabs
Found on predominantly North aspects, this avalanche problem can still be found on all aspects. Past weather has promoted settlement of this problem, but it can still be found lurking in areas where past winds has deposited low density snow. **Location:** All aspects found in both the Alpine and at Treeline. **Possibility:** Triggering of this avalanche problem is possible from light loads such as skiers. Natural avalanches are unlikely. **Size:** If triggered expect these avalanches to be small, and on isolated terrain features large, size 2.

Likelihood

Possible

Expected Size

1 - 1

Valid until: Feb 22nd, 2020 1:00AM