Avalanche Forecast

Issued: Dec 19th, 2018 3:20PM

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

mconlan, Avalanche Canada

South Coast.

Another storm is passing over the region on Thursday, with freezing levels peaking around 2000m. Expect to find touchy conditions at higher elevations. Travel in avalanche terrain is not recommended.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

WEDNESDAY NIGHT: Cloudy with snow above 1200m, accumulation 10 to 15cm. THURSDAY: Cloudy with snowfall at high elevations and otherwise rainfall, accumulation 30 to 50mm, strong to extreme southwest winds, treeline temperature 2Â°c, freezing level rising from 1300m to 2000m over the day. FRIDAY: Partly cloudy, moderate west winds, treeline temperature -4Â°c, freezing level 700m. SATURDAY: Cloudy with snowfall, accumulation 10 to 15cm, moderate to strong southwest winds, treeline temperature -2Â°c, freezing level 1000m.

Avalanche Summary

No new reports of avalanches in the region. In the neighbouring Sea to Sky region, many natural and explosive-controlled avalanches have been reported through the last several days. Similar avalanche activity is likely to be found at high elevations in the South Coast region.We would very much appreciate it if you spend a moment to submit any observations you have to the Mountain Information Network here, even if it is just a photo. Thanks!

Snowpack Summary

Thursday's precipitation will start as snow around 1300 m and then fall as rain at most elevations as freezing levels rise. The rain will fall onto recent dry snow above 1300 m and on rain-soaked snow below 1300 m. For the higher elevation areas, which are generally accessible around Squamish, expect to find storm slabs up to 100 cm thick and even deeper wind-loaded deposits in alpine lee terrain features. Snow depths are over 200 cm in the alpine.

Problems

Storm Slabs

Recent storm snow accumulations over 100 cm may be found at higher elevations. Expect to find even thicker slabs in lee terrain features due to strong winds from the south. More snow and rain on Thursday may make these slabs even touchier.

Watch for signs of instability such as whumpfing, cracking, or recent avalanches.Be alert to conditions that change with elevation.Use caution in lee areas. Recent wind loading have created wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2.5

Loose Wet

The forecast calls for freezing levels to 2000 m. Rain falling on recent new snow may result in the weakening of surface snow and sluffing in steep terrain.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Dec 20th, 2018 2:00PM