Avalanche Forecast

Issued: Jan 12th, 2014 8:03AM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs and Wind Slabs.

catherine brown, Parks Canada

Glacier.

Good group management and conservative terrain choices are essential today as you travel through avalanche terrain. Note avalanche activity and avoid paths that have not avalanched recently.

Summary

Weather Forecast

Flurries are forecast today with freezing levels remaining at valley bottom and moderate SW ridge top winds, gusting to 95 km/h. Another storm moves in tonight into Monday. Heavy precipitation is forecast with freezing levels rising to 1200 m on Monday. Expect strong winds from the west during this storm. Flurries are forecast for Tuesday.

Snowpack Summary

Over 75 cm of high density storm snow at treeline overlies previous lower density layers resulting in a touchy surface slab. Moderate to strong winds are aiding in slab development in exposed terrain treeline and above. The Nov 28th surface hoar layer, down over 2 m, may be reactivated by the rapid loading or step down avalanches.

Avalanche Summary

We have limited observations of a few small natural avalanches up to size 1.5, the occurred overnight. A large cycle of natural avalanche was observed through out the day yesterday. Avalanches were up to size 3.5 depositing snow at the bottom of runnouts. Yesterday, artillery control produced numerous avalanches from all aspects up to size 3.0.

Confidence

Intensity of incoming weather systems is uncertain on Monday

Problems

Storm Slabs

Over 75 cm of heavy storm snow has fallen with moderate/strong southerly winds. This new snow is causing natural avalanches and is very touchy to human-triggering.

The new snow will require several days to settle and stabilize.Choose conservative lines and watch for clues of instability.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 3

Wind Slabs

Strong southerly winds over the last two days has created touchy wind slabs.

Avoid avalanche terrain during periods of heavy loading from new snow and wind.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 13th, 2014 8:00AM