Avalanche Forecast

Issued: Apr 14th, 2018 4:19PM

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

mconlan, Avalanche Canada

Kootenay Boundary.

More snow and high freezing levels are forecasted. Slabs will thicken and the snow will weaken with the warming. Expect the likelihood of triggering avalanches to increase. Treat the hazard as High if you find more than 25 cm of new snow.

Summary

Confidence

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

Weather Forecast

SATURDAY NIGHT: Cloudy with snowfall, accumulation 10 to 15 cm, strong southwest winds, alpine temperature -3 C, freezing level 1500 m.SUNDAY: Cloudy with light snowfall, accumulation 5 to 10 cm, light south winds, alpine temperature 0 C, freezing level 2000 m.MONDAY: Cloudy with snowfall, accumulation 10 to 15 cm, light south winds, alpine temperature -3 C, freezing level 1400 m.TUESDAY: Cloudy with light snowfall, accumulation 5 to 10 cm, light west winds, alpine temperature -3 C, freezing level 1500 m.

Avalanche Summary

On Friday, widespread loose activity was noted in the region. Loose wet was common at lower elevations and loose dry at higher elevations within the recent storm snow. They were generally small to large (size 1 to 2.5), at treeline and alpine elevations, and generally below rocks or in steep southerly terrain. A few small slabs were also noted within the recent storm snow.

Snowpack Summary

40 to 50 cm of recent snow sits on a hard melt-freeze crust. Strong south winds formed wind slabs in lee terrain features at higher elevations. The snowpack below this is generally well-settled and strong.

Problems

Storm Slabs

Snowfall continues, with up to 25 cm forecasted by Sunday afternoon and strong southwest winds. Expect storm slabs to be reactive to both natural and human triggers.

Observe for the bond of new snow with the old surface before committing into avalanche terrain.Avoid avalanche terrain under periods of rapid snowfall or wind-transport loading.Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Loose Wet

Freezing levels could reach 2000 m, which would warm the snow surface and allow precipitation to fall as rain. Loose wet avalanche activity will increase under these conditions.

Avoid steep slopes when air temperatures are warm, it is raining, or the solar radiation is strong.Use caution above cliffs and terrain traps where small avalanches may have severe consequences.