Avalanche Forecast

Issued: Mar 3rd, 2015 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Loose Dry, Wind Slabs and Deep Persistent Slabs.

jon stuart-smith, Parks Canada

Waterton Lakes.

WIth up to 40cm of new snow over the last week the turns are better than they have been in a long time. Avalanche danger will increase as temperatures and SW winds increase on Wed. Paying attention to the changing conditions will be important.

Summary

Weather Forecast

The arctic air will hang around on Tue keeping things cold, dry and only light NE winds. The westerly flow will return on Wednesday and temperatures will start to warm up and strong SW winds. Avalanche activity could increase dramatically with the rise in temperatures and winds.

Snowpack Summary

Another upslope event added 10-15 to the 20cm we received last week. The recent storm came in with mod NE winds creating slabs on W to S slopes. These could be sitting on old windslabs or very slick suncrusts. In sheltered places there is up to 40cm on the Feb 14 crust. Easy sluffing of this new snow was observed in the summit are on Monday.

Avalanche Summary

The new snow has been sluffing out of steep terrain but there has been no evidence of any deeper avalanches.

Confidence

Freezing levels are uncertain

Problems

Loose Dry

With up to 40cm of low density new snow over the last week, any steep slope could see sluffing. These may not be big enough to bury a person but could knock you over and have serious consequences in the wrong place.

Avoid travelling on ledges and cliffs where sluffing may have severe consequences.Be cautious of sluffing in steep terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Wind Slabs

New slabs have developed with the recent snow and NE winds, creating windslabs in places they may not usually be seen. As temperatures warm up and SW build more windslabs on Wed and Thur there will be a spike natural avalanche activity.

Avoid travelling in areas that have been reverse loaded by winds.Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

These slabs continue to stand out as a concern in the TL and ALP areas where there is not a strong Jan 31 crust over them (2200m+). Be particularly mindful in thin snowpack areas where this layer is more likely to be triggered.

Be aware of thin areas that may propogate to deeper instabilites.Carefully evaluate and use caution around thin snowpack areas.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Mar 6th, 2015 4:00PM