Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Apr 7th, 2014–Apr 8th, 2014

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

Kootenay Boundary.

With no overnight refreeze anticipated on Monday night, warming issues are a bid deal right now.

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Tuesday

Weather Forecast

Warm weather is expected to persist through Tuesday before a pulse of precipitation associated with the passage of a cold front is expected Tuesday night, followed by a drop in temperature. Tuesday: Warm. Sunshine expected in the morning, becoming cloudy in the afternoon. Freezing level as high as 2800 m. Winds starting light, becoming moderate SW. Tuesday night: 2-8 mm of rain/sleet/snow with strong SW winds. Wednesday: Lingering flurries in the morning, becoming dry and bright later. Freezing level around 1800 m. Light NW winds. Thursday: Dry. Cloudy with some sunny breaks. Freezing level around 2000 m. Light westerly winds.

Avalanche Summary

On Saturday and Sunday, explosives control resulted in a number of avalanches up to size 2.0 in the Nelson area running in recent storm snow. Some loose wet slides up to size 1.5 were reported from solar aspects.

Snowpack Summary

A recent storm slab of 15-40 cm in depth sits above a 2-5 cm melt-freeze crust that developed last week on all but shaded North aspects in the alpine. This crust has been reported to be very hard ("knife" resistance) in some parts of the region and there may be a layer of surface hoar between it and the new storm snow above. There is now about 75 cm of well compacted snow above the March 10th melt-freeze crust. In some areas the March 10th crust is helping to bridge over the deeply buried late January/early February persistent weak layer. The Jan/Feb deep persistent weak layer continues to be a concern for very large destructive avalanches. Releases on this layer may be more likely during periods of strong solar radiation and/or prolonged warm temperatures at alpine elevations.

Problems

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.