Archived

Avalanche Forecast

Jan 3rd, 2017–Jan 4th, 2017

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

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Purcells.

Be extra cautious around south slopes: they're weak, wind-loaded, and getting hit by the sun.

Confidence

High - The weather pattern is stable

Weather Forecast

WEDNESDAY: Sunny with cloudy periods, light north winds, alpine temperatures around -18.THURSDAY: Sunny with cloudy periods, light west winds, alpine temperatures around -16.FRIDAY: Cloudy, light west wind, alpine temperatures around -14.

Avalanche Summary

On Monday, avalanche reports were limited to a few size 2 wind slabs on southerly aspects that were triggered naturally and by explosives. Wind slabs may remain reactive to human triggers in specific areas, such as the immediately lee of ridges and sun-exposed slopes.

Snowpack Summary

Strong winds over the weekend had an extensive effect in exposed terrain. Expect scouring and wind slabs in unusual places, as the winds shifted from west to northeast during the arctic outbreak. Sunny weather is likely making the snow extra touchy on south-facing slopes. The mid-December facet/surface hoar layer can be found buried 30-60 cm deep. This layer has been unreactive recently, although snowpack test suggest it may still be possible to trigger in shallow snowpack areas. The lower snowpack is well bonded and features a thick rain crust near the ground that appears to be dormant.

Avalanche Problems

Wind Slabs

Reverse wind loading has formed wind slabs in unusual places. Southerly aspects are extra suspect thanks to northerly winds and sunny weather.

Minimize exposure to steep, planar south facing alpine slopesAvoid travelling in areas that have been reverse loaded by winds.Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2