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Avalanche Forecast

Jan 21st, 2015–Jan 22nd, 2015
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
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
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
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

Regions: Sea To Sky.

Thursday may literally be 'The Calm Before the Storm(s)'. It looks like a wet and warm weekend ahead.

Confidence

Good

Weather Forecast

Synopsis: A series of frontal systems will affect the south coast over the next few days. The first and weakest system grazes the region tonight bringing light amounts of snow (5-10 cm) and relatively cool temperatures (freezing level around 1000-1400 m). The next, much stronger system dumps heavy snow/rain beginning on Thursday night maybe 20-40 mm. The freezing level shoots to 2000-2300 m with strong SW winds. Another wet and warm pulse should arrive sometime on Saturday bringing heavy rain and freezing levels up to 2500 m. Yikes!

Avalanche Summary

Recent avalanche activity progressed from a limited avalanche cycle on Saturday and Sunday (mainly from wind loaded terrain), to several explosive and rider triggered avalanches up to size 2 on Monday and Tuesday. Conditions will start to change heading into the weekend. Warm temperatures and rain could tip off another round of wet avalanche activity by Friday and/or Saturday.

Snowpack Summary

Up to 50 cm of settled storm snow sits on a hard crust and/or surface hoar layer. Previous strong W-SW winds redistributed snow in exposed terrain creating deep and dense wind slabs in lee features. The new snow seems to be bonding well to the crust, which is most pronounced between about 1500 m and 2200 m. The distribution of the surface hoar seems spotty across the region, but some operators found it to be widespread in their tenure before it was buried. Deeper snowpack weaknesses have fallen off the radar, but they could be reawakened with a very heavy load (like a cornice fall or wind slab) in the wrong spot (like a thin snowpack area).

Avalanche Problems

Wind Slabs

Thin fresh wind slabs could form on Thursday, while older stubborn wind slabs lurk beneath. Use caution in steep lee terrain. 
Use ridges or ribs to avoid pockets of wind loaded snow.>Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3