Archived

Avalanche Forecast

Feb 3rd, 2018–Feb 4th, 2018

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

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

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: Sea To Sky.

New snow totals are uncertain in this weather pattern. Danger ratings are based on 5-15 cm of new snow. If snowfall amounts are greater than 20 cm, the danger is CONSIDERABLE and time to dial back your terrain use while avoiding overhead hazard.

Confidence

Low - Forecast snowfall amounts are uncertain on Sunday

Weather Forecast

Sunday: 5-10cm of snow Saturday overnight to Sunday with another 5-10 cm possible during the day / Moderate gusting strong west winds / Freezing level at 1500mMonday: Mainly cloudy with isolated flurries / Light north westerly winds / Freezing level at 1200mTuesday: Isolated flurries (5cm possible) / Light to moderate south westerly winds / Freezing level 1000m.

Avalanche Summary

On Saturday we received reports of a skier triggered size 1.5 avalanche near Whistler on a north west aspect around 2100m.On Friday ski cutting produced several size 1 soft slabs on immediate down wind (lee) features. Explosives control on Thursday and Friday triggered cornices at ridge crests, mostly size 1.5 - 2.

Snowpack Summary

Over the past two days 7-12 cm of new snow has fallen as temperatures warmed up to +2 at tree line on Saturday afternoon. Winds, however, were strong to extreme from the south, creating fresh wind slabs in exposed downwind (lee) terrain. At lower treeline and below, generally light amounts of snow or rain now overlie a melt-freeze crust which formed during last Monday's warm storm. The new snow adds to the 170cm of snow that fell during the last few weeks of January. These series of storms were accompanied by strong to extreme winds which resulted in extensive scouring and impressive cornice growth in upper elevation terrain. These accumulations sit on a crust from mid-January which generally shows signs of bonding to the overlying snow; however, it has the potential to "wake-up" with a large trigger such as a cornice fall.Below this, the snowpack is thought to be generally strong and well-settled.

Avalanche Problems

Storm Slabs

Areas with high amounts of new snow could be primed for storm slabs whereas areas that see less snow may be more susceptible to wind slabs. Wet loose avalanches are possible below tree line if precipitation falls as heavy rain.

Stay off recent wind loaded areas until the slope has had a chance to stabilize.Be alert to conditions that change with elevation.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Cornices

Recent heavy snowfall and high winds have formed fragile new cornices. These monsters may surprise with nasty consequences. Use extra caution around ridge crests.

Falling cornices may trigger large avalanches on the slopes below.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1.5 - 2.5