Avalanche Forecast

Issued: Mar 9th, 2020 2:00AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Persistent Slabs, Storm Slabs and Loose Dry.

Jesse Percival, VIAC

Vancouver Island.

Reports from steep skiing on North aspects at 1400 meters indicate that the new snow that has fallen is very loose and dry. This snow is easy to trigger on steep terrain, producing Loose dry avalanches up-to size 1. One soft storm slab was trigger on a steep convex roll and was size one. A skier trigger a size one storm slab avalanche on a steep convex roll near Mount Beecher. Previous to triggering this avalanche the party reported seeing other signs of instability , cracking and settling. There was no involvement, injuries or lost gear in any of these reports.

Summary

Past Weather

A flurry of convective storm activity brought to the forecast region a variety of weather conditions all with snowfall. Western regions experienced amounts in excess of 40 cm and Eastern 10 to 20 cm. Temperatures remained relatively low with freezing levels remaining below 1000 meters.

Weather Forecast

Periods of unstable weather will deliver a variety of conditions, expect Tuesday a low pressure to bring increased wind and moderate snowfall.Monday 5 cm of new snow. Winds Light Southwest. Freezing levels 1000 meters.Tuesday 15 to 30 cm of new snow. Winds Strong Southwest. Freezing level 1200 meters.Wednesday 5 cm of new snow. Winds light to moderate Northwest. Temps -5 to -8. Freezing level 1000 meters.

Terrain Advice

Careful and cautious route finding when transitioning into wind effected convex rolls or steep terrain.Default to lower angled terrain if you observe wind drifted snow, active snow transport, or snowfall amounts that exceed 30 centimeters.

Snowpack Summary

A refresh of new storm snow overlies previous old snow surfaces. In protected areas this snow is low density and well preserved. In areas that are exposed to the wind and sun , the snow is settling and are becoming consolidated and slab like.

Snowpack Details

Surface: New snow of up to 40 overlies over a thin sun crust on solar aspects and on old hard snow on non solar.
Upper: 30 to 100 cm of settled storm snow with a few thin crusts sandwiched between on solar aspects.
Mid: An old crust with weakening snow crystals above and below the crust as it continues to degrade.
Lower: Well settled and dense.

Confidence

Moderate - A high degree of variability between forecast snowfall amounts in western and eastern zones of the forecast area.

Problems

Persistent Slabs

Down between 35 to 100 cm this decomposing crust is the remnants of surface hoar and is becoming less reactive and is approaching dormancy. Location: On North aspects and found in both the Alpine and at Treeline. Possibility: Triggering of this avalanche problem is unlikely to possible from light loads such as skiers. Natural avalanches are unlikely. Size: If triggered expect these avalanches to be large on isolated terrain, size 3.

Likelihood

Possible

Expected Size

1 - 1

Storm Slabs

Found on predominantly North thru to East aspects, avalanche problem has formed and will continue to as new low density snow begins to settle over a variety of crusts. Location: All aspects found in both the Alpine and at Tree line. Possibility: Triggering of this avalanche problem is likely to very likely from light loads such as skiers. Natural avalanches are possible to likely. Size: If triggered expect these avalanches to be large size 2, and on isolated terrain features very large, size 3.

Likelihood

Possible

Expected Size

1 - 1

Loose Dry

This avalanche problem will be predominately small but in terrain with traps even a small avalanche can be hazardous. Expect during daytime warming and sunshine this problem to become moist and may be more hazardous. Location: All aspects found and all elevations. Possibility: Triggering of this avalanche problem is likely to very likely from light loads such as skiers. Natural avalanches are possible to likely. Size: If triggered expect these avalanches to be small size 1, and on isolated terrain features large, size 2.

Likelihood

Possible

Expected Size

1 - 1

Valid until: Mar 10th, 2020 2:00AM