Avalanche Forecast

Issued: Apr 10th, 2019 4:16PM

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

swerner, Avalanche Canada

Lizard-Flathead.

Isolated pockets of reactive wind slab may be found at upper elevations on Northerly aspects. The sun packs a punch this time of year and even small doses can initiate loose wet avalanches.

Summary

Confidence

Moderate -

Weather Forecast

Unsettled weather leading into the weekend bringing a mix of sun and cloud and some convective precipitation. Snow amounts are extremely hard to nail down.TONIGHT: Possible snow amounts 4-10 cm. Alpine temperatures -2 and freezing levels 1300 m. Ridgetop winds moderate from the southwest.THURSDAY: A mix of sun and cloud with alpine temperatures near 0 degrees and freezing levels 1700 m. Ridgetop winds light from the southwest.FRIDAY: A mix of sun and cloud with alpine temperatures near 1 degree and freezing levels 1700 m. Ridgetop winds moderate primarily from the southwest.SATURDAY: Cloudy with a trace of snow. Alpine temperatures near 0 degrees and freezing levels 1800 m. Ridgetop winds will generally be light with strong gusts from the southwest.

Avalanche Summary

On Wednesday, loose wet avalanches up to size 1 were reported from steep alpine features. Snowfall amounts are uncertain for the next 24 hours and if the region receives more then 15 cm it could increase the avalanche hazard.

Snowpack Summary

10-15 cm of accumulated snow from the past few days is moist and has turned to shmoo from daily warming at treeline and below. A supportive crust sits below the recent snow above 1400 m. Below 1400 m the snowpack is becoming isothermal. During the heat of the day, especially under direct sun, the snow surface becomes moist or wet almost everywhere. The exception being high elevation north facing features. Steep, north facing, alpine terrain may still hold a cold, dry, snowpack where isolated reactive wind slabs may exist and a well settled slab rests on weak facets (sugary snow). Although unlikely, human triggering of persistent slabs on this layer may still be possible, especially in rocky alpine terrain with a shallow or highly variable depth snowpack.

Problems

Loose Wet

The likelihood of loose avalanches increases as temperatures warm through the day and/or if the sun comes out for period of time.

A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.Loose avalanches may start small but they can grow and push you into dangerous terrain traps.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Wind Slabs

Wind slabs on higher elevation North facing slopes may be reactive to human triggers.

Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.

Aspects: North, North East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Apr 11th, 2019 2:00PM