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

Dec 19th, 2017–Dec 20th, 2017

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 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.

Regions

Glacier.

Skier or Rider triggered avalanches are likely today. Now is a good time to step back and make conservative terrain choices.

Weather Forecast

A Low-Pressure system slides South of Rogers Pass, while a large High-Pressure moves in from the NE. As these two weather patterns duke it out, we'll accumulate 5-10cm of new snow, moderate Northerly winds and cold temperatures in the -10 range. 5cm tonight and plummeting temperatures into the future as the High-Pressure dominates our region.

Snowpack Summary

40cm of storm snow now overlies the Dec 15th Surface Hoar/Persistent Weak Layer. On steep solar aspects, there is a sun crust also buried under the new snow, reaching well into the Alpine from last week's inverted temperatures. Throughout the snowpack there are multiple crusts, which are currently bonded well to neighboring layers.

Avalanche Summary

A Widespread natural avalanche cycle occurred yesterday morning up to size 2.5 in the highway corridor. Avalanches were mainly size 1.5 to 2 and all failing as a soft slab on the Dec 15th Surface Hoar Layer. Avalanches initiated on all aspects and elevations yesterday, see attached pic of a below tree line slab avalanche. low elevation avalanches

Confidence

Due to the number and quality of field observations

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.