Avalanche Forecast

Issued: Jan 15th, 2018 4:43PM

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

jmcbride, Avalanche Canada

Sea To Sky.

Heavy snow, rain and strong winds are expected for the forecast period. Expect touchy storm slabs at elevations that receive snow. At lower elevations watch for wet snow avalanches in steep, rain-soaked terrain.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

MONDAY NIGHT: Rain changing to snow. Precipitation 4-8 mm. Ridge wind strong, south. Temperature +1. Freezing level lowering to 1500mTUESDAY: Snow. Accumulation 10-20 cm. Ridge wind strong, southwest. Temperature -2. Freezing level 1200 m.WEDNESDAY: Heavy snow. Accumulation 30-50 cm. Ridge wind strong, south. Temperature -1. Freezing level 1500 m.THURSDAY: Snow. Accumulation 25-40. Ridge wind strong, southwest. Temperature -3. Freezing level 1200 m.

Avalanche Summary

Warm alpine temperatures on Sunday produced numerous naturally triggered loose wet and wet slab avalanches mostly in the size 1-1.5 range, and a few up to size 2 on solar aspects.

Snowpack Summary

Warm temperatures at all elevations are consolidating the snowpack and making the surface moist on all but north aspects. At elevations above approximately 1500 m precipitation from the previous storm fell as snow, while below that elevation, rain fell.Â Below the new storm snow, a thick crust that was buried on January 6th is now buried 30-50 cm below the surface. This crust exists up to about 2000m elevation.Beneath the January 6 crust, the lower snowpack is generally strong and well settled.

Problems

Storm Slabs

Loading from new snow and strong winds will create widespread storm slabs. Loose wet and wet slab avalanches will be the concern where rain has soaked the snow. A release near the surface may still have the potential to step down to a deeper layer.

Use extra caution on slopes if the snow is moist or wet.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely - Certain

Expected Size

1 - 2

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