Archived

Avalanche Forecast

Jan 19th, 2020–Jan 20th, 2020

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Cariboos.

New slabs may be touchy and the warming trend has the potential of waking up the buried weak layer. Travel conservatively during this period of uncertainty.

Confidence

Moderate - Uncertainty is due to how buried persistent weak layers will react with the forecast incoming weather.

Weather Forecast

SUNDAY NIGHT: Cloudy with snowfall, accumulation 3 to 10 cm, moderate to strong southwest wind, alpine temperature -2 C, freezing level rising to 1000 m.

MONDAY: Cloudy with snowfall, accumulation 5 to 10 cm, moderate to strong southwest wind, alpine temperature -3 C, freezing level 1200 m.

TUESDAY: Cloudy with snowfall, accumulation 2 to 5 cm, light to moderate south wind, alpine temperature -5 C, freezing level below valley bottom.

WEDNESDAY: Morning snowfall then a mix of sun and cloud, accumulation 1 to 3 cm, light southwest wind, alpine temperature -7 C, freezing level below valley bottom.

Avalanche Summary

Avalanche activity has quieted down over the past few days, but new snowfall, strong southwest wind, and a rise in air temperature will likely produce new slabs, with the most reactive being in exposed terrain at and above treeline.

There hasn't been an avalanche reported on the persistent slab problem since January 13. The likelihood of triggering this layer could increase as the air temperature rises on Sunday night into Monday.

Snowpack Summary

The south of the region received around 10 to 20 cm of snow on Saturday and another 10 to 20 cm of snow may accumulated Sunday night into Monday. The snow is accompanied by strong southwest wind as well as an increase in the freezing level, meaning that the snow may form cohesive slabs relatively quickly. The touchiest slabs will likely be in lee terrain features at and above treeline.

The main concern over the past couple of weeks has been a layer of surface hoar buried 60 to 120 cm deep. Although an avalanche has not been reported on this layer in the past six days, the likelihood of triggering it may increase as the air temperature warms.

Terrain and Travel

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Extra caution for areas experiencing rapidly warming temperatures for the first time.
Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

Avalanche Problems

Storm Slabs

Around 10 to 30 cm of recent snow will have accumulated in the region by Monday afternoon, with associated strong southwest wind and relatively warm air temperature. This weather recipe will form new slabs, with the touchiest likely being at and above treeline in lee terrain features near ridges.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2

Persistent Slabs

A layer of surface hoar is buried 60 to 120 cm deep. As the air temperature rises on Monday, the likelihood of triggering this layer may increase. Use added caution in clearings around treeline during periods of warming.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3