Archived

Avalanche Forecast

Mar 16th, 2016–Mar 17th, 2016

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: South Coast.

Strong sunshine will increase avalanche danger during the day. Plan your route to minimize exposure to big sun-drenched slopes in the afternoon.

Confidence

High

Weather Forecast

THURSDAY: Mainly sunny. The freezing level is around 1400-1600 m. Ridge winds are moderate from the northeast. FRIDAY: Mainly sunny. The freezing level should jump to around 1800-2000 m and ridge winds are light gusting to moderate from the southeast. SATURDAY: Increasing cloud. The freezing level is around 1800 m and winds remain light.

Avalanche Summary

Cornices continue to pop off with regularity. Some are triggering slabs below and others are not. In the north of the region on Sunday, a cornice collapse triggered a size 3.5 deep slab avalanche which failed on glacier ice. A second size 3.5 deep persistent slab was observed nearby on Tuesday likely occurring around the same time). Forecasts sunshine and warming will cause cornice activity to increase and result in loose wet sluffing from steep sun exposed slopes.

Snowpack Summary

Up to 75cm of snow fell over the last week or so. This snow is reported to be settling and gaining strength, but lingering storm instabilities may still exist, especially in recently wind loaded terrain features. Cornices are reported to be large and fragile. Expect to encounter a sun crust or moist snow on sun-exposed slopes depending on the time of day. The mid and lower snowpack are generally strong and well-settled. Below 1200m the snowpack is reported to be isothermal.

Avalanche Problems

Wind Slabs

We could see fresh wind slabs form in immediate lee terrain from moderate northeasterly winds on Thursday. Sun and afternoon warming may increase the sensitivity of triggering a slab.

Minimize exposure to sun exposed slopes when the solar radiation is strong. >Be cautious as you transition into wind affected terrain. >The new snow may require several days to settle and stabilize. >

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 4

Cornices

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

Cornices become weak with daytime heating. >Extra caution needed around cornices with current conditions.>

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 5

Loose Wet

Loose wet sluffing is likely in steep sun-exposed terrain during the day.

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

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

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 3