Avalanche Forecast

Issued: Nov 11th, 2015 4:07PM

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

brian webster, Parks Canada

Banff Yoho Kootenay.

A significant storm is forecast to hit the area on Friday. Pay attention to the rising avalanche danger

Summary

Weather Forecast

Flurries with light accumulations and freezing levels near valley bottom forecasted for Thursday. A significant storm is forecasted for Thursday night through Friday with accumulations of 30-40 cm of snow at treeline, high winds, and freezing levels rising to 1600 m. An avalanche cycle is expected on Friday.

Snowpack Summary

35-45 cm of unconsolidated snow exist at treeline elevations throughout the forecast area. A 5mm layer of surface hoar that was reported in some areas has been buried by several cm of new snow today (November 11 surface hoar). Some soft wind slabs exist at higher alpine elevations.

Avalanche Summary

Over the past five days slabs and loose snow avalanches (up to sixe 2.5) have been triggered and are running naturally from alpine features. Yesterday at Bow Summit a size 1.5 avalanche was remotely triggered on the ground, and on the Wapta a group remotely triggered a size 2 on Mt. Olive.

Confidence

Forecast snowfall amounts are uncertain on Friday

Problems

Wind Slabs

Avalanches up to 50 cm deep are being triggered in many areas in high alpine, glaciated terrain. Avoid wind loaded features in the alpine.

Be careful with wind loaded pockets while approaching and climbing ice routes.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Loose Dry

The entire snowpack is unconsolidated, and loose avalanches have been observed to have run through confined gully areas - this is something ice climbers should keep in mind as they consider any overhead hazards to their routes.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Nov 12th, 2015 4:00PM