Avalanche Forecast
Issued: Feb 2nd, 2021 4:20PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Dry.
Ian Jackson,
Avalanche control is planned on Mt Dennis (Field backroad and beer ice climbs), Mt Stephen and Mt Field in Yoho on Wednesday February 3rd. No access to these areas on Wednesday!
Summary
Weather Forecast
Cooling temperatures, easing winds and a brief clearing on Wednesday as the overall flow shifts to the NW. Thursday and Friday are showing continued light precipitation (3-5 cm per day), cool temperatures and gradually building alpine winds into the strong range from the NW at 3000m elevation. Possibility of an upslope on Friday.
Snowpack Summary
Another 10-20 cm of new snow on Tuesday brings totals to 30-60 cm since Jan. 27th. This snow is low density below treeline, but is forming slabs up to 100 cm deep above treeline where the wind is doing some light drifting. The lower snowpack has a series of persistent weak layers that remain dormant. Snowpack amounts at treeline are 150-220 cm
Avalanche Summary
An avalanche cycle up to size 2.5 occurred today in the Lake Louise/Yoho/93N area with an intense cell of precipitation that dropped 15-20 cm in a few hours. Many of these were storm slabs or loose dry avalanches out of steep cliffy terrain.
Sunshine was reporting less new snow but a period of strong south winds building touchy windslabs
Confidence
Due to the number of field observations
Problems
Storm Slabs
An avalanche cycle to size 2.5 occurred on Tuesday primarily in the northern region that received the most recent storm snow.
Southern areas got more wind and this problem was acting more like a windslab primarily in alpine and treeline areas
- Use caution in lee areas in the alpine and treeline. Storm snow is forming reactive slabs.
- Steep unsupported terrain and slope convexities are the likely locations to awaken the storm slab.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
Up to 60 cm of storm snow sluffs easily in steep terrain. Ice climbers should avoid all gully climbs on Wednesday and skiers watch your sluff on all steep slopes.
- Be careful of loose dry power sluffing in steep terrain.
- Be aware of party members below you that may be exposed to your sluffs.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 3rd, 2021 4:00PM
