Avalanche Forecast

Southwest flow ushers in plenty of wind, moisture and a rising freezing level.

THURSDAY NIGHT: Freezing level at valley bottom, moderate west/southwest wind, trace of snow possible.

FRIDAY: Overcast, freezing level beginning at valley bottom rising to about 1000 m, moderate to strong west/southwest wind, trace of snow possible during the day with 1 to 5 cm Friday night. 

SATURDAY: Overcast, freezing level beginning at valley bottom rising to about 900 m, moderate to strong southwest wind, trace of snow possible during the day with 4 to 10 cm Saturday Night. Freezing level is expected to climb through the night. 

SUNDAY: Overcast, freezing level beginning around 1400 m climbing to about 1700 m during the day, strong to extreme southwest wind, 5 to 15 cm of snow at upper elevations with rain in the valleys. 

This surprisingly large human triggered avalanche from near Wells Wednesday is a great example of the strange conditions that are created by reverse wind loading. Huge thanks to the reporting party for sharing this with the community. No other avalanche activity to report from this week.

Last weekend, observers reported several small human-triggered wind slabs at treeline and alpine elevations in areas west in the region (see the MIN reports here and here). A MIN report near Valemount reported small loose dry avalanches on steep terrain in the trees.

Earlier in February, there was widespread avalanche activity on a weak layer of buried surface hoar, mostly on treeline features (see some photos in the MIN reports here, here, and here). 

Light flurries have begun to accumulate over a variety of surfaces including surgary facets, feathery surface hoar, and wind-affected snow that formed as a result of last week's dry, cold weather. New snow totals ranging from 10-15 cm may be found in areas west and north in the region, with 5 cm falling in the south.

40-70 cm of snow from February is settling over a reactive weak layer of surface hoar buried in late January. In some areas, there may be two of these layers in close proximity (buried Jan 24th and Jan 30th). Reactivity on these surface hoar layers has primarily been observed at treeline and in "treeline-like" features, like cutblocks, that are below treeline. On steep south-facing terrain, this layer may consist of facets on a sun crust.  

Additional weak layers may present in the lower snowpack, but are not a concern in most areas until we see significant snow loading or rapid warming. 

• Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.
• Be aware of the potential for large avalanches due to the presence of buried surface hoar.
• Extra caution is needed around cornices under the current conditions.