Avalanche Forecast

A short lived ridge will bring dry warm weather on Thursday.

WEDNESDAY NIGHT: Partly cloudy, moderate south wind, treeline temperatures drop to -5 C.

THURSDAY: Mix of sun and cloud, strong south wind, freezing level climbs to around 1800 m with treeline temperatures around -1 C.

FRIDAY: Cloudy with scattered flurries and 5-10 cm of new snow, strong south wind, freezing level climbs to 1700 m with treeline temperatures around -2 C.

SATURDAY: Another 5 cm of new snow by the morning then a mix of sun and cloud during the day, light southwest wind, freezing level climbs to 1400 m with treeline temperatures around -5 C.

While we are uncertain about the current reactivity of persistent slab problems in the Cariboos, the combination of an overall weak snowpack structure with warming temperatures and sunshine suggest this is a time to be extra cautious in avalanche terrain. Read the latest Forecaster Blog for concerns about the warming.

Although there have been limited recent field observations, we have good reason to remain suspect of persistent weak layers producing large destructive avalanches. On Sunday, there was a report of a size 2 human-triggered wind slab avalanche in the east of the region (MIN report) and this MIN report from just north of the region in the McGregors shows a very large (size 3.5) persistent slab avalanche that likely occurred on Sunday as well. There were several significant reports of avalanche activity last week between Feb 23 and Feb 25 including:

• A natural size 2.5 avalanche that ran full path in the Dore River area on Feb 25 (MIN report).
• A very large human-triggered avalanche on Tuesday near Valemount that was initiated from a wind-loaded start zone at the top of a large alpine feature. It propagated for hundreds of meters along a ridge and ran to valley bottom. Thankfully the rider was able to escape unharmed.
• A fatal avalanche just outside of the region, northeast of Valemount, in Swift Creek on Feb 23. The avalanche was a size 3.5 and is suspected to have failed on the late January persistent weak layer. The report can be found here.

Surface conditions are a mix of wet and crusty snow at low elevations and south-facing slopes, hard wind affected snow at upper elevations, and settling powder in some shaded and sheltered terrain.

Over the past few weeks there have been multiple deeper weak layers producing large avalanches, but we have little to no information about how these layers have trended over the past few days. Layers of concern include a 50-100 cm deep layer of facets that was buried in mid-February, a 50-150 cm deep layer of surface hoar from early February that was most prevalent at treeline (and existed as a facet/crust combination on steep south-facing terrain), and finally another persistent weak layer from late January that is now roughly 100-200 cm deep.

• Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
• Avoid being on or under sun exposed slopes.
• Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
• Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
• Be especially cautious as you transition into wind affected terrain.