Archived

Avalanche Forecast

Apr 6th, 2017–Apr 7th, 2017

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

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

Regions: South Rockies.

Freezing levels and precipitation amounts are uncertain. Danger may be CONSIDERABLE during periods of heavy rain.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain on Friday

Weather Forecast

FRIDAY: About 5-15 mm of precipitation with strong southwest wind and snow line fluctuating between 1500 and 2000 m.SATURDAY: Mix of sun and cloud with isolated flurries, moderate southwest wind, freezing level up to 1900 m after overnight freeze.SUNDAY: Cloudy with a chance of getting clipped by a storm to the south, freezing level around 1700 m.

Avalanche Summary

Small loose wet avalanches were reported in the southeast part of the region on Thursday. On Wednesday, explosive control produced two small wind slabs in steep alpine terrain in the southeast part of the region. Small avalanches are expected on Friday with the incoming storm.

Snowpack Summary

Moderate rainfall is expected at least up to treeline on Friday. Rain falling on a warm snowpack has the potential to produce loose wet avalanches in any steep terrain. At higher elevations, new snow and wind will form fresh wind slabs and cornices will grow bigger. The snowpack is well settled and transitioning into spring conditions. The bottom third of the snowpack is composed of weak facets, but this deep persistent weakness has not been reactive for a few weeks.

Avalanche Problems

Loose Wet

Rain at lower elevations will cause loose wet avalanches in steep unsupported terrain features.

Minimize exposure to avalanche terrain during periods of heavy loading from new snow, wind, or rain.Use extra caution on slopes if the snow is moist or wet.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Wind Slabs

Strong winds and light snow will form fresh wind slabs at higher elevations where the snow is still dry.

Use ridges or ribs to avoid pockets of wind loaded snow.Be alert to conditions that change with elevation.Avoid freshly wind loaded features.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Cornices

Cornices are large and may fall off naturally with daytime warming or rain.

Give cornices a wide berth when travelling on or below ridges.Minimize exposure to overhead hazard from cornices.Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 2 - 2