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

Jan 18th, 2014–Jan 19th, 2014

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

Northwest Inland.

Confidence

Poor

Weather Forecast

A strong upper ridge of high pressure will dominate the weather pattern for a week or more. However, a weakening Pacific front will move through the ridge Saturday resulting in light precipitation through Saturday evening.Saturday Night: Freezing Level: 1100m; Precip: 1/3mm 2/6cm Wind: Strong, WSunday: Freezing Level: 800m; Precip: Nil; Wind: Decreasing throughout the day.Monday: Freezing Level: Inverted, below freezing at Valley Bottom, above freezing from 1200 2600m Precip: Trace; Wind: Mod, SWTuesday: Freezing Level: Inverted, below freezing at Valley Bottom, above freezing from 1200 2600m Precip: Nil; Wind: Mod, SW

Avalanche Summary

A large avalanche cycle that was most active in the northern portion of the region wrapped up January 15th. All aspects and elevations were involved with natural avalanches running to size 3.5. Most of these avalanches likely ran on the early January surface hoar layer. In the Southern portion of the region a few small slab avalanches were reported from steep leeward terrain.

Snowpack Summary

Previously strong winds have resulted in widespread wind damaged/loaded snow at and above treeline. The buried surface hoar layer at treeline and the basal facets in thin rocky areas at treeline and in the alpine remains a concern.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.