Avalanche Forecast

Issued: Apr 11th, 2018 4:18PM

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

swerner, Avalanche Canada

South Coast.

Reactive storm slabs and loose dry avalanches exist in the alpine and the treeline. Loose wet avalanche activity expected at lower elevations. Another blast of winter will arrive on Friday.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

Weather models are showing the possibility of accumulated precipitation amounts up to 40 mm by Wednesday night. Come Friday a (light) atmospheric river reaches the region bringing freezing levels near 1600 m and upwards to 50 mm. Thursday: Cloudy with sunny periods. No significant precipitation. Ridgetop winds moderate from the southwest and freezing levels 1000 m. Friday: Stormy. Light precipitation in the am and increasing throughout the day with 40 -50 mm by the evening and another 40 mm overnight. Ridgetop winds strong from the South and freezing levels rising to 1600 m. Saturday: Stormy. Mix of rain and snow elevation dependent. Ridgetop winds strong from the South and freezing levels 1500 m.

Avalanche Summary

We have received very little information on avalanche activity for this region. From the little we have heard, there were no new avalanches to report from Wednesday. Forecast heavy precipitation should mean that the likelihood of triggering avalanches is on the rise.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

Rain is now falling as snow at upper elevations building reactive storm slabs which sit over a predominant thick crust. It is difficult to predict where and when rain will switch to snow, but expect the transition to happen and by Wednesday and most precipitation will fall as snow above 1300 m.At below treeline elevations, a spring snowpack exists. Rain has saturated and weakened the upper snowpack. Forecast rain will continue this trend.

Problems

Storm Slabs

Heavy snow at upper elevations is building new, reactive storm slabs. Watch for new slabs in areas when the rain switches to snow. The snow will fall with strong southwest winds, so expect thicker slabs in lee features.

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Loose Wet

Rising freezing levels and rain will rapidly weaken the snow surface and initiating loose wet avalanches.

Avoid steep slopes when air temperatures are warm, it is raining, or the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Apr 12th, 2018 2:00PM