Avalanche Forecast
Issued: Feb 7th, 2021 8:00AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Kate Ryan,
Winds have begun to shift north in some locations in the park- keep an eye for reverse loading today.
Summary
Weather Forecast
Arctic air is on the way! Temps dipping to -30 C by Wednesday....
Today: A mix of sun and cloud. No precip. Alpine high -17 C. Light NW wind.
Tonight: Mainly cloudy with isolated flurries. Trace of precip. Alpine low -22 C. Light W wind.
Monday: Cloudy with sunny periods. Alpine high -22 C. Light west wind.
Snowpack Summary
Snow from the Feb 2 storm has been redistributed by strong south winds, followed by a switch to northwesterlies in some locations. The Jan 26 persistent weak layer is buried 60-80cm and consists of decomposing surface hoar in sheltered areas and a thin crust on solar aspects. The mid and lower snowpacks are strong, with no current concerns.
Avalanche Summary
Yesterday, field teams were able to trigger small, very soft slab avalanches over a crust on a south aspect at treeline. Yesterday evening, an isolated natural avalanche cycle occurred on steep, south aspects in the alpine where a switch to northerly winds was seen.
Confidence
Problems
Wind Slabs
A period of reverse loading from northerly winds occurred yesterday evening, adding to the windslab problem created over the past week by moderate to strong south winds.
- Be cautious as you transition into wind affected terrain.
- Be careful with reverse loaded pockets of wind slab at ridgeline.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
The Jan 26th layer down 60-80cm is consist of decomposing surface hoar in sheltered areas and a crust on solar aspects. Reactivity appears to be decreasing on this layer, though it remains reactive to human triggers in isolated areas at Treeline.
- Use caution on open slopes and convex rolls at treeline where buried surface hoar may be preserved.
- Recent snow may be more sensitive to human triggering on solar aspects where it sits on sun crust
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Feb 8th, 2021 8:00AM
