Avalanche Forecast
Issued: Jan 30th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
cgarritty,
Avalanche Canada
Avalanche danger is expected to become HIGH before the end of the day as heavy precipitation, strong winds, and rising temperatures make their way into the region. Be aware of conditions changing over the day, especially in overhead terrain.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Thursday night: Cloudy with flurries bringing 5-10 cm of new snow. Strong southwest winds.
Friday: Cloudy with increasing snowfall bringing 15-25 cm of new snow, transitioning to rain below about 1700 metres, continuing overnight. Strong southwest winds. Alpine high temperatures approaching 0 as freezing levels climb to 1800-2000 metres.
Saturday: Cloudy with continuing flurries bringing 10-15 cm of new snow and 2-day snow totals to 30-50 cm, closer to 10 cm below 1500 metres. Light to moderate northwest winds. Alpine temperatures dropping to -10 as freezing levels fall from 1700 metres to valley bottom over the day.
Sunday: Mainly cloudy with isolated flurries and a trace of new snow. Light southwest winds. Alpine high temperatures around -10.
Avalanche Summary
On Tuesday, there was a report of a size 2.5 persistent slab avalanche on a north aspect at 1900 m in an area southwest of Valemount.
On Saturday there was one notable report of a size 3 persistent slab avalanche southwest of Valemount that was remotely triggered (triggered from a distance) by a group of people.
Over the past week there have been reports of numerous size 1-2.5 storm slab avalanches on all aspects at all elevations. These were mostly natural avalanches, with a few explosives triggered avalanches as well.
Looking forward, heavy precipitation, strong winds, and rising temperatures will promote increasing natural avalanche activity on Friday. During this time, occasional persistent slab releases such as those mentioned above may result from avalanche activity in surface snow layers.
Snowpack Summary
20-35 cm of new snow is expected to fall at higher elevations in the region by end of day on Friday. The new snow will cover wind affected recent snow at alpine and upper treeline elevations while rain saturates the surface below about 1700 metres.
The mid and lower snowpack are generally well settled and strong, however there is a weak layer of surface hoar currently buried 70 to 130 cm deep. This layer has produced very few recent avalanches in the region, though it could still be triggered in isolated areas.
Terrain and Travel
- Storm slab size and sensitivity to triggering will likely increase through the day.
- Be alert to conditions that change with elevation.
- Avoid exposure to overhead avalanche terrain during periods of heavy loading from new snow, wind or rain.
Problems
Storm Slabs
Rapid loading of new snow during Friday's storm will build new storm slabs at higher elevations. Forecast strong winds and warm temperatures will speed slab formation as new snow accumulates.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Wet loose avalanches will be in increasing problem on Friday at lower elevations that see rain instead of snow accumulating. This problem will affect increasingly high elevations over the day.
Aspects: All aspects.
Elevations: Below Treeline.
Likelihood
Expected Size
Valid until: Jan 31st, 2020 5:00PM
