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 21st, 2013–Jan 22nd, 2013

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

Regions

South Columbia.

Confidence

Fair - Timing of incoming weather is uncertain on Wednesday

Weather Forecast

Monday night and Tuesday: Another day with the upper ridge pattern. Few high clouds with valley clouds above the main valleys, strong Westerlies becoming moderate, the inversion will start to erode and freezing levels also starting to drop. Wednesday: A system coming from the Pacific will begin to affect the region in the afternoon bringing moderate precipitation, cooler temperatures and lowering freezing level to the surface, with moderate SW winds.Thursday: Lingering precipitation from the system with moderate to strong W winds. Temperatures staying cool.

Avalanche Summary

A few natural slab avalanches up to size 2.5 released on steep solar aspect with the exception of one on a NE aspect.  Several loose snow avalanches up to size 2 on S facing slopes were also reported. A glide crack release produced a size 2.5 avalanche below treeline on a NE facing slope.

Snowpack Summary

A variety of surfaces await the next snowfall; windslabs in the alpine, facets and surface hoar in specific areas and a suncrust on South facing slopes. The windslabs in the alpine and at treeline are settling and slowly breaking down due to surface facetting. The surface hoar layer below the 40-60 cm of generally well settled snow is becoming less of a concern for the professionals but still produces some sudden planar shears amongst other resistant planar and break shears.  A strong mid-pack overlies a weak facet/crust layer near the base of the snowpack, which is now considered inactive.

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.

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.