Avalanche Forecast

Issued: Dec 20th, 2019 1:00AM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs.

VIAC Jesse Percival, VIAC

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No new avalanches observed or reported

Summary

Past Weather

Small snowfall events where followed by periods of clear and cold. These early seasons weather events have contributed to both basal instabilities (facets) and surface hour. Subsequent snowfall has buried the surface hoar.

Weather Forecast

A strong winter weather systems is followed by a period of unsettled weather. Friday 15 to 30 cm precipitation , Winds Strong from the South east , Freezing levels 1000 meters.Saturday 5 to 10 cm precipitation , Winds Light from the North east, Freezing levels 1100 meters.Sunday trace amounts of precipitation , Winds light from the east, Freezing levels 700 meters.

Terrain Advice

During periods of high hazard, travel in avalanche terrain should be avoided. Storm slab sensitivity should begin to reduce on Sunday and cautious and conservative route finding should be practiced in avalanche terrain. Early season low snow conditions exist at lower elevations, hazards such as creeks and rocks are just hiding under the snow-pack. Slow your pace and give plenty of time to maneuver around these hidden hazards.

Snowpack Summary

Low snow pack conditions exist with depths below tree line at 40 to 50 cm and treeline depths of 60 to 80 cm. Its likely that the snow pack in the alpine has exceeded 100 centimeters.During recent field observations, continual underfoot settlement was felt and audible whumping was heard. Cracks formed around the skis when cresting all but the smallest feature and foot penetration was to ground.Snow-pack testing and profiling at 1500 m on a N asp revealed a well developed surface hoar layer down 60 cm and during numerous compression tests produced sudden collapse results. Hard compression tests pulled the column to ground and revealed facets.

Snowpack Details

  • Surface: unconsolidated new snow
  • Upper: numerous shears within sightly settled snow
  • Mid: buried surface hoar size 2-6 mm
  • Lower: basal faceting

Confidence

Low - field observations limited

Problems

Storm Slabs

An icon showing Storm Slabs
Found at all elevations and aspects, expect this avalanche problem to be touchy to light triggers such as skiers. The chance of these avalanches being triggered is very likely and when triggered will produce avalanches size two or greater.

Likelihood

Possible

Expected Size

1 - 1

Valid until: Dec 21st, 2019 1:00AM