Archived

Avalanche Forecast

Apr 15th, 2018–Apr 16th, 2018

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

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: Northwest Inland.

When the sun comes out it will quickly weaken the surface snow. Watch for signs that the snow is heating up such as pin-wheeling or the snow surface becoming moist.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

MONDAY: Mix of sun and cloud. Light northeasterly ridgetop winds. Alpine temperature -3. Freezing level around 1100 m.TUESDAY: Mix of sun and cloud. Light southwesterly ridgetop winds. Alpine temperature -3. Freezing level around 1100 m.WEDNESDAY: Mostly cloudy with sunny breaks. Light southwesterly ridgetop winds. Alpine temperature -2. Freezing level around 1200 m.

Avalanche Summary

No new avalanches were reported in this region on Saturday. On Wednesday, an explosive triggered size 2.5 deep persistent slab on a west aspect between 1000-1300 m was reported near Ningunsaw.

Snowpack Summary

Lingering wind slabs on convex features below ridgetops may still be reactive to human triggers.Weak layers buried around March 19th are roughly 40 cm below the surface (up to 100 cm in deeper snowpack areas). These weak layers include surface hoar on shaded aspects at high elevations and hard crusts on solar aspects and below treeline.Near the bottom of the snowpack, sugary facets are found in shallow, rocky snowpack areas. Storm slab avalanches have "stepped-down" to these facets and produced very large avalanches in the far northern parts of the region.

Avalanche Problems

Loose Wet

When the sun comes out it will quickly weaken the new snow and cause loose wet avalanching on steep solar slopes.

Cornices become weak with daytime heating. Give them a wide berth both from above and below.Watch for signs that the snow is heating up such as pin-wheeling or the surface snow becoming moist.Minimize exposure to sun exposed slopes when the solar radiation is strong.

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

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 2

Wind Slabs

Wind slabs may still be reactive in isolated locations.

Use caution when transitioning into wind effected terrain.Avoid areas that look freshly loaded with snow; especially convex features below ridgetops.Avoid shallow, rocky areas where the snowpack transition from thin to thick.

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 1.5