Avalanche Forecast

Issued: Apr 19th, 2017 5:50PM

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

mgrist, Avalanche Canada

South Coast Inland.

Conditions are touchy at higher elevations, with storm slabs bonding poorly to the Easter crust. Dial back your terrain use until conditions settle out.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

Light precipitation amounts on Wednesday through to Thursday afternoon. Fine weather on Friday.THURSDAY: Snow overnight Wednesday and then tapering by noon Thursday (accumulations of 5-15cm possible above 1500m in the north). Winds moderate southerly.FRIDAY: Sunny with cloudy periods. Freezing level rising to 2200m. High temperatures to +6 Celsius. Winds light southerly.SATURDAY: Wet weather returns around noon (5-10mm by the evening). Freezing levels falling to 1700m. Winds moderate southerly.

Avalanche Summary

On Wednesday we had reports of several loose wet avalanches to Size 2 running on north aspects in the alpine in the Duffey zone. The new snow was especially reactive to ski cutting on solar (south) aspects, running easily on the Easter crust. On Tuesday we had reports of small, loose wet avalanches, pinwheeling and plenty of avalanche debris in the Coquihalla zone. See here for the MIN report.

Snowpack Summary

This region has received 7-10cm of snow above 1500m on each of the past three days. Dry snow (20-30cm) can still be found above 2100m, however, it sits on the Easter temperature crust and is proving reactive.At lower elevations the new (moist) snow is sliding easily on the Easter crust and is the primary concern. Below treeline, the snow is moist and typically has not been refreezing overnight: Loose wet avalanches remain a concern in this elevation band.Cornices remain large in some areas and could trigger large avalanches when they fail (especially when warmed by the sun). The fatal accident near Lions Bay a week ago illustrates the danger of cornices breaking off, and the large avalanches they can trigger.

Problems

Storm Slabs

New storm snow is not bonding well to the (Easter) sun crust. Conditions have been touchy, especially on south aspects and wind loaded pockets.

Recent storm snow has formed touchy slabs, especially where it sits on a firm crust.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Cornices

Recent snow and wind have created large cornices. Minimize your exposure to cornices when it is cold and cloudy and completely avoid them when it is warm and/or sunny.

Falling cornices can trigger large avalanches.Give cornices a wide berth when travelling on or below ridges.

Aspects: North, North East, East, South East, South.

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Loose Wet

Loose wet avalanches are more likely at lower elevations where the snowpack may be isothermal and precipitation falls as rain. Even small slides can have serious consequences.

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

Aspects: North, North East, East, South East, South.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 20th, 2017 2:00PM