Avalanche Forecast
Issued: Jan 15th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Loose Wet and Persistent Slabs.
kdevine,
Avalanche Canada
The stormy weather pattern continues for the Northwest Coast, keeping danger elevated. Avoid avalanche terrain.
The likelihood of natural avalanches will increase throughout the day with heavy snow and strong wind.
Summary
Confidence
Weather Forecast
FRIDAY NIGHT - Mainly cloudy with a few flurries / southwest wind, 40-60 km/h / alpine low temperature near -5 / freezing level 1000 m, and near valley bottom in the far north (Ningunsaw)
SATURDAY - Snow, 10-20 cm, with another 10-20 cm overnight / southwest wind, 50-70 km/h / alpine high temperature near -2 / freezing level 1000 m in the south, near valley bottom in the north
SUNDAY - Flurries, 5-10 cm / southwest wind, 30-60 km/h / alpine high temperature near -2 / freezing level 1000 m in the south, near valley bottom in the north
MONDAY - Mainly cloudy / southwest wind, 30-60 km/h / alpine high temperature near -2 / freezing level 1500 m in the south, 1000 m in the north
Avalanche Summary
Continued stormy weather will mean that storm slabs are anticipated to be widespread and natural avalanches are expected. Wet loose avalanches may still be possible at lower elevations in the south.
There were a few natural and explosives triggered size 1-3 avalanches reported in the north of the region on Thursday.
There were a few natural avalanches up to size 3 reported in the north of the region on Wednesday. There was also one remotely triggered size 3 persistent slab avalanche reported in the north of the region.
There was a natural avalanche cycle reported on Tuesday, as well as numerous explosives triggered avalanches up to size 2.5 and a few human triggered size 1 avalanches.
On Monday, there were reports of widespread natural and explosives triggered avalanches up to size 3. The largest avalanches were reported in the north of the region where there has been more recent snow. The avalanches being reported closer to Terrace were generally in the size 1-2 range.
Snowpack Summary
10-20 cm of snow is expected during the day on Saturday, bringing recent storm snow totals to around 80-140 cm.
The snow is likely wet up to treeline in the south of the region. Further north, the snow may be wet or moist below treeline towards Bear Pass, and to a lesser extent around Ningunsaw.
In the Shames area, a weak layer of surface hoar has been reported in sheltered areas down around 120-180 cm.
A bit further north in the Nass/Sterling/Beaupre areas, there is potentially still concern about an older weak layer overlying a crust that is now roughly 180-200 cm deep.
In the far north of the region, there is concern about weak snow at the bottom of the snowpack.
Terrain and Travel
- Avoid all avalanche terrain during periods of heavy loading from new snow and wind.
- Avoid avalanche terrain during periods of heavy rain.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Another 20 cm of snow is expected on Saturday with strong winds. Storm slabs are likely widespread and reactive.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Rain below treeline in the south of the region may produce wet loose avalanches. Avoid steep slopes and terrain traps at low elevations where the snow is wet.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Persistent Slabs
There are a few different persistent weak layers being reported throughout the region. They are all generally buried between 100-200 cm and tend to consist of either surface hoar or crusts with faceted snow sitting on them.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 16th, 2021 4:00PM
