Current Snowpack Synopsis
Pow. That’s right, one of the slowest starts in recent years has turned around since late January and has delivered 135mm of snow water equivalent to the snowpack. Mt Fidelity’s weather station at 1905m is now reading 265cm.
36cm of recent storm snow has fallen in since midnight Feb 18, which was accompanied by moderate to strong S-SW flow. This recent storm snow overlies colder and lower density storm snow from late last week (Totalling 50-80cm of storm snow.). Below this exists a melt freeze crust on solar steep solar aspects.
The mid-pack is gaining strength and rounding with the continued precipitation and mild temperatures we’ve had recently. the January surface hoar layers are rounding, but can still be found in isolated areas down 1.5-2m.
However the November facets are still prominent at the base of the snowpack. The facets are showing signs of rounding, but there is still a considerable step in resistance between them and the overlying snow. The November facets are more pronounced in shallow rocky areas.
What’s been riding well
Over the past week there has been exceptional storm riding paired with a couple of fantastic days of high pressure. Deep trail breaking has been a recent theme.
Over the weekend with the recent storm inputs of precipitation and wind, sheltered areas at tree line and below have been the place to be. In exposed areas, storm slabs have been created in immediate lee features.
The recent melt freeze crust on steep solar aspects is hardly felt under foot.
Recent Avalanche Activity
This has been a significant storm cycle and has produced natural avalanches to size 3.5 near Rogers Pass. There was a size 4 artillery controlled avalanche that failed on a deep persistent weak layer as well. Natural cornice failures have been observed recently too. Sluffing in terrain over 35 degrees has been frequent with rider traffic.
Incoming weather and avalanche forecast
Tuesday will bring another pulse of snow to Rogers Pass accompanied with a frontal passage and strong northerly winds later in the day. An arctic ridge will establish itself over Roger Pass Wednesday and Thursday dropping temperatures significantly.
Cornices: Cornices have grown significantly in recent weeks and there have been numerous natural cornice failures that have resulted in avalanches up to size 3 in, or around Rogers Pass. Give them respect and a wide birth when you are travelling under them. Be cautious of solar input.
Storm slabs: Recent moderate to strong winds have caused storm slabs in exposed areas in alpine, tree line and below tree line features. There has been a natural cycle to size 3.5 over the weekend and these storm slabs will be reactive to rider traffic in the next few days. Watch out for reverse loading with the incoming northerly flow.
Dry Loose: Watch out for sluffing in terrain over 35 degrees. Sluffs have been running fast and far over the weekend.
Deep Persistent Slabs: The November facets are still very much a concern across the backcountry ski / snowboard industry in the Columbia Mountains. They have produced controlled and natural avalanches to size four in the past couple of days. They will need a bit of time to adjust to the new load that has been applied to them. Be aware of overhead hazard. The November facets are more pronounced in shallow, rocky features. Professionals are still maintaining a conservative mindset with this low probability/ high consequence avalanche problem.
Backcountry skiing and splitboarding are inherently dangerous activities. Decisions made about terrain in which you may choose to travel should be based on real time data you’ve collected firsthand, not on this report. Conditions in the mountains change rapidly, please be aware that things will probably have changed since this report was written.