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Avalanche Forecast

Feb 19th, 2014–Feb 20th, 2014
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
3: Considerable
The avalanche danger rating below treeline will be considerable
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
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
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: Sea To Sky.

Confidence

Fair - Due to the number of field observations

Weather Forecast

A frontal wave will move onto the coast late today followed by a series of weak disturbances that may bring light precipitation, then the weather pattern begins to dry out and cool off.Wednesday evening: Mostly cloudy, light locally moderate snowfall, some parts of the forecast area may receive 5-10cm of snow, freezing level at valley bottom overnight, ridge top winds 30 gusting to 60km/h SW-WThursday: Freezing level at or near valley bottom. Possibility of a trace of precipitation, ridge top winds from the W 30 gusting to 75km/h Friday: Freezing level at valley bottom. Nil to trace precipitation in the forecast for Friday. Mostly light ridge top winds with the occasional gust to moderate

Avalanche Summary

We're still seeing reports of natural and explosive triggered avalanches throughout the forecast region. All are storm slab avalanches and occurred mostly at tree line and above. These appear to be running on the Feb. 10th facet/crust/surface hoar combination. Skier remote and skier controlled avalanches have diminished, but are still highly possible.

Snowpack Summary

Recent snowfall amounts exceed 1.75m during the past week and has now settled into a storm slab with a typical thickness of 60-100cm. The storm slab is overlying a variety of old weak surfaces that developed during the past cold, dry spell. It consists of weak facets, surface hoar, a scoured crust, wind pressed snow, or any combination of these. A poor bond exists between the storm slab and these old surfaces. Much of the recent storm snow has been redistributed into wind slabs on lee slopesOf particular concern is the combination of buried facets on a crust that has been unusually reactive at tree line and below. Avalanche activity, whumpfing and snowpack tests at these elevations are showing easy sudden planar shear results on the facet/crust combo. Strong to extreme winds are redistributing the new snow into deeper, and denser wind slabs on lee slopes.The mid and lower snowpack are generally strong and well-settled. Basal facets and depth hoar are likely to exist in some parts of the region, but triggering has become unlikely.

Avalanche Problems

Storm Slabs

Natural avalanche activity has diminished, but with the large amount of new snow skiers/riders should excercise caution conservative route finding, especially in recently wind loaded terrain. This may not be the time to ride "Big Lines".
Stick to simple terrain and be aware of what is above you at all times.>Use caution in lee areas in the alpine and treeline. Recent wind loading have created wind slabs.>Pay attention to overhead hazards like cornices.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 4