Avalanche Forecast

Issued: Mar 10th, 2012 7:57AM

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

Tim Haggarty, Parks Canada

Waterton Lakes.

Heat and wind have triggered small slides that have pulled out deeper persistent slabs. Continued warm temps (Saturday and Sunday), strong winds, and a bit of snow are forecast. Consider the effects of these factors above you and under your skis.

Summary

Problems

Wind Slabs

Strong Westerly winds have built hard slabs in open lee areas. Due to the hard character of these slabs the potential for wide propagations is increased. Extra caution with large planar lee slopes.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Storm Slabs

The recent storm snow is settling with the effects of wind and heating forming a stiffer slab. These shallow slabs are weakened with daytime heat and will be sensitive to light loads: skiers, snow rolling off of rocks and trees or moist sloughs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

Sun Crusts and Surface Hoar now down 50 to 100 cm. Watch daytime heating on solar slopes above the crusts. Isolated areas on Northerly slopes protected from the sun and wind may hold surface hoar. If triggered these slabs would be large.

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Mar 13th, 2012 5:00PM