Archived

Avalanche Forecast

Nov 17th, 2011–Nov 18th, 2011

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

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

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: Northwest Coastal.

This bulletin is based on limited data. Local variation in conditions and danger levels are likely to exist. To produce more accurate forecasts, we need information. Please send an email to [email protected].

Confidence

Poor - Due to limited field observationsfor the entire period

Weather Forecast

Friday: Mostly clear with freezing levels at sea level and Alpine temperatures as low as -17 Celcius. Strong Northeasterly outflow winds developing throughout the day.Saturday: Increasing clouds and warming trend as winds shift to westerly, but freezing levels remaining at sea level.Sunday: Light snowfall increasing throughout the day with gradual warming

Avalanche Summary

I suspect there was a decent natural cycle during the storms earlier this week, especially on wind-loaded slopes. The possibility of human-triggered wind and storm slab avalanches is expected to remain for the forecast period.

Snowpack Summary

Another 10-15cm adds to the recent storm snow totals. Varying temperature, precipitation intensity, and wind throughout the recent storms have probably resulted in weaknesses strewn throughout the top metre or so. However, the relatively warm post-storm temperatures on Thursday should favor settlement and strengthening. The mid and lower snowpack is generally well settled and strong, with an old rain crust near the ground.

Avalanche Problems

Wind Slabs

Near ridgecrests and terrain breaks, and in cross-loaded gullies.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 2 - 5

Storm Slabs

Steep unsupported slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 4