Archived

Avalanche Forecast

Mar 7th, 2016–Mar 8th, 2016

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

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

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: South Rockies.

Lingering wind slabs are expected to remain reactive to human-triggering on Tuesday. Large cornices will become weak with daytime warming and sun so avoid cornice exposed slopes in the afternoon.

Confidence

Moderate

Weather Forecast

A mix of sun and cloud is expected for Tuesday with the possibility of isolated flurries. Freezing levels are expected to reach around 1500m in the afternoon and alpine winds are forecast to be moderate from the southwest to west. Mostly sunny conditions are expected for Sunday with afternoon freezing levels around 1500m and light alpine wind. A weak storm system is currently forecast to bring 5-10mm of precipitation to the region on Thursday with freezing levels climbing to around 2000m.

Avalanche Summary

On Sunday there were several size 1 loose wet avalanches observed below treeline. No other new avalanches were reported, but this may speak to a lack of observers rather than actual conditions. Recent wind slabs are expected to be lingering at higher elevations on Tuesday.Â

Snowpack Summary

Rainfall on Sunday was reported to around 2100m elevation. The snow surface was reported to be soaked below treeline and dense moist storm snow was reported at treeline. With overnight cooling, a melt-freeze crust is expected at some mid-mountain elevations. In the alpine, strong southwest winds have redistributed the recent storm snow into wind slabs on leeward features. Cornices are also reported to be huge and weak. The mid and lower snowpack are generally well settled and there are currently no major weak layers of concern within the snowpack.

Avalanche Problems

Wind Slabs

Lingering wind slabs in the alpine may remain reactive to human-triggers, especially on steep, unsupported features.

Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Cornices

Large cornices are expected to be fragile and may fail naturally with daytime warming and sun exposure. Not only are they a hazard in themselves, but also a heavy trigger for slabs on the slope below.

Extra caution needed around cornices with current conditions.>Cornices become weak with daytime heating, so travel early on exposed slopes.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 4