Avalanche Forecast

Archived

Apr 4th, 2015–Apr 5th, 2015

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Northwest Coastal.

Use caution in big terrain. Weak layers buried in the snowpack are still a concern. The potential for large destructive avalanches still exists in some areas. If you have observations you'd like to share with other riders, click here.

Confidence

Fair - Forecast snowfall amounts are uncertain

Weather Forecast

5-10cm today tapering off early Sunday morning. Daytime high freezing levels are expected to hover around 1300 m for Friday and Saturday and a bit higher on Sunday. Alpine winds are expected to belight throughout the weekend.

Avalanche Summary

No recent reports of avalanches have been received

Snowpack Summary

45-70 cm of recent settled storm snow is bonding slowly to a variety of old snow surfaces including a layer of surface hoar and facets buried on March 25th. This weakness, now down approximately 40 to 60cm is very touchy with a high propensity for propagating fractures, especially where the buried surface hoar exists. The problems seems more touchy in the northern part of the region, but has been reported throughout the northwest coastal area. Weaknesses have also been found within the recent storm snow with snowpack tests producing moderate sudden results in the top 20cm. The early March facet/crust persistent weakness is now down around a metre and appears unreactive with snowpack tests.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.