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Avalanche Forecast

Feb 24th, 2013–Feb 25th, 2013
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
4: High
The avalanche danger rating at treeline will be high
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
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
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: Sea To Sky.

Confidence

Fair - Due to variable snowpack conditions

Weather Forecast

Sunday night and Monday: Heavy snowfall switching to broken cloud on Monday / Moderate to strong west winds becoming light northwesterly on Monday / Freezing level at 1000mTuesday: Light snowfall / Light southwest winds / Freezing level at 900mWednesday: Moderate to heavy snowfall / Strong southwest winds / Freezing level at 1000m

Avalanche Summary

A widespread natural avalanche cycle to size 3 was observed in response to heavy loading from wind and snow on Friday. I would expect ongoing avalanche activity with forecast weather and the current weak snowpack structure.

Snowpack Summary

Heavy amounts of recent snow and strong winds have created deep and potentially destructive storm slabs. Underneath the new snow, you may find surface hoar that was buried on February 20th. Field reports suggest that it is reactive in many areas throughout the region, particularly at treeline and sheltered alpine terrain where broad shooting cracks were observed. Where it exists, surface hoar will certainly prolong the reactivity and destructive potential of the newly developed slab. The mid and lower snowpack layers are generally strong and well settled.The current weather will likely be forming new cornices. Expect cornices to be large and unstable.Total snow depths vary from around 400 cm in the south to around 180 cm in the north.

Avalanche Problems

Storm Slabs

Moderate to heavy snowfall and strong winds forecast for Sunday will contribute to ongoing storm/ wind slab instabilities. Triggering will most likely occur in wind-loaded terrain or in areas where buried surface hoar exists.
Be cautious as you transition into wind affected terrain.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Dig down to find and test weak layers before committing to a line.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 5