Avalanche Forecast

Issued: Apr 18th, 2018 4:19PM

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

jmcbride, Avalanche Canada

South Coast.

Warming and sun on Thursday will weaken the recent snow and increase the likelihood of triggering avalanches. Be extra cautious on south-facing slopes. Avoid exposing yourself to hazard from large slopes or cornices overhead while its sunny or warm.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TONIGHT: Clear. Ridge wind light, south. Temperature at treeline near +2. Freezing level 1600 m.THURSDAY: Mostly sunny. Ridge wind light, southwest. Temperature at treeline near +3. Freezing level 1600 m.FRIDAY: Cloudy. Rain changing to snow beginning in the evening. Precipitation 15-30 mm. Ridge wind light, south. Temperature at treeline near 0. Freezing level 1500 m, lowering to 1000 m.SATURDAY: Mostly cloudy, snow ending. Accumulation 10-20 cm. Ridge wind moderate, southwest. Temperature at treeline near -1. Freezing level 1200 m.

Avalanche Summary

We have received very little information on avalanche activity for this region. From what we have heard, skiers could easily trigger small loose wet avalanches on Monday. Natural loose wet avalanches were also observed in treeline and alpine terrain, particularly on southerly aspects. Over the weekend, large slab avalanches were also observed on the North Shore mountains that may have released during the storm on Friday. Read MIN report hereFurther north near Squamish reports indicated sun-induced natural activity on Sunday in alpine terrain.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

Above about 1200 m, 50 to 60 cm of moist snow sits on a predominant crust that formed at the beginning of April. The snow below this is well-settled and strong.Below 1200 m, a spring snowpack exists.

Problems

Loose Wet

The sun and warming temperatures on Thursday will rapidly weaken the snow surface. Expect loose wet avalanches, particularly on steep southerly terrain and near rocks. Watch your overhead exposure, as wet slides can quickly gain mass and grow large.

Use extra caution on slopes if the snow is moist or wet.Avoid steep slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Storm Slabs

Recent snowfall has formed storm slabs, which sit on a melt-freeze crust in most areas. Sun and warming could produce moist slabs failing on the crust. Also be cautious on or below corniced ridges. Cornices can become weak with sun and warming.

Be cautious as you transition into wind-affected terrain.Pay attention to overhead hazards like cornices, which could trigger slabs on slopes below.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Apr 19th, 2018 2:00PM