Avalanche Forecast

Issued: Mar 17th, 2016 8:32AM

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

pmarshall, Avalanche Canada

Sea To Sky.

Avalanche danger will rise on solar aspects during the day. Hunt for good dry snow and lower hazard on the north side of the mountain!

Summary

Confidence

High

Weather Forecast

FRIDAY: Mainly sunny. The freezing level should jump to around 1800-2000 m and ridge winds are light to moderate from the east. SATURDAY: Overcast with a chance of light precipitation. The freezing level is around 1800-2100 m and winds remain light. SUNDAY: Moderate snow or rain with freezing levels near 1800 m and light ridge winds.

Avalanche Summary

Recent avalanche activity is primarily limited to natural and explosive-triggered cornice falls and small loose wet sluffs from steep sunny terrain. Some cornice falls have been large (size 3), but only a few triggered slabs on the slope below. On Tuesday, one explosive triggered cornice triggered a 1-2 m deep slab on the slope below that released on an old weakness. Forecast sunshine and warming will likely increase cornice activity and cause loose wet snow to continue shedding from steep sun exposed slopes.

Snowpack Summary

The snow surface consists of a sun crust or moist snow on sun-exposed slopes (depending on the time of day), dry settled powder on shady slopes (cool temperatures have maintained good snow quality), and pockets of fresh wind slab in lee and cross-loaded terrain features near ridge crests. In general, the snowpack is strong and well-settled throughout with no notable persistent weaknesses. Cornices are reported to be large and fragile.

Problems

Wind Slabs

Light to moderate outflow winds (from the north) may have reverse loaded slopes near ridge crests creating touchy pockets of wind slab on southerly aspects.

Be cautious as you transition into wind affected terrain. >Minimize exposure to sun exposed slopes when the solar radiation is strong. >

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Cornices

Cornices are reported to be large and weak. Natural cornice releases are possible with sun exposure and warming.

Give cornices a wide berth when travelling on or below ridges.>Extra caution needed around cornices with current conditions.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 5

Loose Wet

These loose wet sluffs can gain significant mass and have the potential to drag you places you might not want to go.

Be cautious of sluffing in steep terrain.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 18th, 2016 2:00PM