Avalanche Forecast
Regions: Cariboos.
Minimize exposure to large looming cornices weakening in the sun on Monday. The new snow will be prone to point releases on south facing slopes and wind slabs may be found in immediate lees of exposed alpine terrain features.
Confidence
Moderate - Uncertainty is due to the limited number of field observations.
Weather Forecast
Sunday night: Clear. Light to moderate northwest wind. Alpine temperature -8. Freezing level valley bottom.
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 1900 m.
Wednesday: 10-20 cm new snow. Strong southwest wind easing to light. Alpine temperature around -10. Freezing level 1400 m.
Avalanche Summary
Small (size 1) loose dry avalanches on steep solar aspects and small loose wet at elevations with above-freezing temperatures can be expected on the new snow on Monday. Isolated wind slabs may also be triggerable by riders.
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.Â
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
10-20 cm of recent snow may have seen some wind effect in immediate less of exposed alpine features. Reports indicate it is bonding well to underlying surfaces which include wind affected snow in the alpine or crust on solar aspects and below 1900 m. Below this elevation and on solar aspects the new snow dusts crusty surfaces down to 1500 m. Below 1500 m, 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
- Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.
- Watch for signs of slab formation throughout the day.
- Rocks will heat up with daytime warming and may become trigger points for loose wet avalanches
- Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
Avalanche Problems
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: Possible
Expected Size: 2 - 3
Wind Slabs
Wind slabs will be most likely be isolated to immediate lees of ridgecrests and roll-overs in wind exposed alpine terrain.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood: Unlikely
Expected Size: 1 - 1.5
Loose Wet
Loose avalanches can be expected in the new snow on steep solar aspects and at elevations where air temperature rises above freezing. Below treeline, loose wet avalanches are possible where snow did not refreeze overnight.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 1.5