Avalanche Forecast

Issued: Mar 27th, 2019 4:19PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Loose Wet and Wind Slabs.

cgarritty, Avalanche Canada

South Columbia.

Recent snowfall resupplied a pair of avalanche problems affecting the region. Be mindful of avalanche danger increasing in sync with daytime warming.

Summary

Confidence

High -

Weather Forecast

Wednesday night: Cloudy with clear periods. Light east winds.Thursday: A mix of sun and cloud. Light east winds shifting northeast. Alpine high temperatures around -1 with freezing levels to 1900 metres, 1000 metres overnight.Friday: A mix of sun and cloud. Light variable winds. Alpine high temperatures around 0 with freezing levels to 2100 metres., 1500 metres overnight.Saturday: A mix of sun and cloud with cloud increasing over the day. Light southwest winds. Alpine high temperatures around 0 with freezing levels to 2100 metres, 1600 metres overnight.

Avalanche Summary

Reports from Tuesday showed skier traffic, ski cutting and explosives control yielding mainly small (size 1-1.5) storm slab releases, with slab depths of 10-20 cm. North to northeast aspects were the focal point and wide fracture propagations in these results were attributed to a poor bond between the new snow and the previous surface of crust.Looking forward, lingering wind slabs may remain reactive to human triggering and may become touchier with daytime warming. Meanwhile, an ample supply of new snow is in place to reinvigorate loose wet avalanche problems as sunshine and warming take hold each day.

Snowpack Summary

10 to 20 cm of new snow from Tuesday's storm has buried a surface of melt-freeze crust in most areas above 1500 metres. Below this elevation the new snow buried variably moist or crusty surfaces.Precipitation as rain continued to saturate the snowpack that is increasingly isothermal (slushy and cohesionless) and disappearing rapidly below about 1100 metres.The remainder of the snowpack is generally consolidated and strong. Exceptions may exist on north aspects above 2000 m, where a gradually strengthening layer of faceted grains buried 50 to 70 cm deep may still be preserved below an overlying slab of old and hard wind-affected snow.

Problems

Loose Wet

New snow has resupplied our loose wet avalanche problem. Rising temperatures and sunshine will destabilize surface snow on Thursday, especially on steep, sunny slopes. Larger avalanches become possible during peak warming.

This problem may affect shaded aspects where air temperatures exceed 0 degrees.Avoid exposure to terrain traps, where the consequences of a small avalanche could be serious.Start and finish early to reduce your exposure to avalanche terrain during the heat of the day.

Aspects: East, South East, South, South West, West.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Wind Slabs

New snow and south winds formed new wind slabs at higher elevations during the storm. This problem increases with elevation and is variable throughout the region with areas of locally enhanced new snow accumulation.

Be careful around wind loaded pockets near ridge crests and roll-overs.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: North, North East, East, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 28th, 2019 2:00PM