Avalanche Forecast

Issued: Jan 15th, 2018 4:38PM

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

Avalanche Canada jmcbride, Avalanche Canada

Rain mixed with heavy snow and strong winds are expected during the forecast period. At upper elevations new snow will form touchy storm slabs.  At lower elevations, loose wet and wet slab avalanches will be a concern on rain-soaked, steep slopes.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

MONDAY NIGHT: Rain. Precipitation 8-12 mm. Ridge wind extreme, south. Temperature +4. Freezing level 1500 m.TUESDAY: Mix of rain and snow. Accumulation 20-30 cm. Ridge wind strong, southwest. Temperature near 0. Freezing level 1300 m.WEDNESDAY: Rain mixed with snow. Accumulation 30-50 cm. Ridge wind extreme, south. Temperature +1. Freezing level 1600 m.THURSDAY: Snow. Accumulation 35-45 cm. Ridge wind strong, southwest. Temperature near 0. Freezing level 1200 m.

Avalanche Summary

Last Tuesday a skier was injured in a loose, wet avalanche on the North Shore mountains when the top 10-15 cm of wet snow released on the January 8th crust. On Saturday ski cutting produced loose wet sloughs in the top 5-10 cm of moist snow. On Friday explosive control produced a size 1 avalanche that released a 45 cm thick slab on a weak layer just above the January 7th crust.

Snowpack Summary

The upper snowpack consists of moist and wet snow and three prominent crusts (January 10th, January 8th an January 7th crusts) from recent warm weather and rain events.  The most notable layer is the January 7th rain crust, which is now buried 40-60 cm deep. The bond at this interface will likely gain strength over time; however, professionals are monitoring this layer as it has the potential to produce large avalanches in isolated terrain.The snowpack depth at 1000 m is about 150 cm and many early season hazards are still present.

Problems

Storm Slabs

An icon showing Storm Slabs
The combination of heavy wet snow and strong winds are the perfect recipe for widespread storm slab formation. At lower elevations where rain may be the predominant form of precipitation loose wet and wet slab avalanches will be the concern.
If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Use extra caution on slopes if the snow is moist or wet.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

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