Avalanche Forecast
Issued: Apr 3rd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Cornices.
ahanna,
Avalanche Canada
Winter is still hanging on up there, with a fresh hit of snow arriving overnight. The new snow may be reactive in wind loaded features or where it sits over a crust. Check out our latest forecaster blog on managing these not-quite-yet-spring conditions.
Summary
Confidence
Weather Forecast
Highest snowfall amounts will be on southwest facing slopes in the northern part of the region. Below the freezing level, precipitation will fall as rain.
Saturday night: 5-20 cm new snow. Moderate to strong southwest wind. Alpine temperatures around -6. Freezing levels 1000 m.
Sunday: Partly cloudy with scattered flurries. Light northwest wind. Alpine high temperatures around -5. Freezing level 1500 m.
Monday: Sunny. Light to moderate west wind. Alpine high temperatures around -2. Freezing level 1900 m.
Tuesday: Cloud increasing. Wind increasing to moderate to strong southwest. Alpine high temperatures around -2. Freezing level 2000 m.
Avalanche Summary
No new avalanches were reported in the region over the past couple of days, but reports from the neighboring North Columbias on Wednesday included small (size 1) natural and skier triggered loose wet and slab avalanches on south aspects, running on a recent crust layer. One recent natural size 2 cornice failure was also noted.
A couple of avalanche involvements were reported on Monday. We really appreciate this MIN report of a size 1.5 skier triggered storm slab on a northeast aspect around treeline. Thankfully no one was injured.
We regret to report a fatality on Eureka Peak, east of Williams Lake on March 29. A human-triggered cornice failure resulted in a size 2.5 slab avalanche. It is important to remember to stay well back from ridgetops that might be corniced and to avoid slopes with overhead cornice exposure especially under the current conditions where recent rapid growth has made them large and fragile.
Snowpack Summary
5-20 cm of new snow arrives overnight with moderate to strong southwest wind. This has likely added to wind affected surfaces and cornices in the alpine and to settled dry snow on sheltered, shaded aspects above about 1900 m. Below this elevation and on solar aspects the new snow dusts crusty surfaces down to 1500 m. Below this elevation, the moist snowpack is quickly diminishing.
Recent warm weather is expected to have helped old persistent weak layers heal, including a few crusts buried over the last month as well as a facet layer 150 cm deep from the mid-February cold snap.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Dial back your terrain choices if you are seeing more than 20 cm of new snow.
- Extra caution is needed around cornices under the current conditions.
- A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
Problems
Storm Slabs
New snow arriving overnight with moderate wind may result in some fresh wind slabs by Sunday morning. They will be most likely be isolated to immediate lees of ridgecrests and roll-overs in wind exposed alpine terrain. They may be most reactive where they sit over a crust.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices become weak with daytime warming. Cornice falls are dangerous in their own right and they can also trigger slabs on slopes below.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 4th, 2021 4:00PM
