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

Mar 3rd, 2020–Mar 4th, 2020

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

Regions

Lizard-Flathead.

Watch for fresh wind slabs forming in alpine terrain and continue to give cornices wide berth.

Confidence

Moderate - Forecast snowfall amounts are uncertain.

Weather Forecast

TUESDAY NIGHT: A cold front crossing the region will most likely deliver just 5 cm of snow but there's potential for local enhancement of up to 15 cm, strong west wind, freezing level drops to valley bottom with alpine temperatures dropping to -8 C.

WEDNESDAY: Cloudy in the morning then some sunny breaks in the afternoon, moderate west wind with strong gusts, freezing level rises from valley bottom to 1200 m, alpine temperatures around -5 C.

THURSDAY: Sunny, freezing level climbing from valley bottom to 1800 m in the afternoon, moderate southwest wind, alpine temperatures around -1 C.

FRIDAY: Increasing cloud with light flurries in the afternoon, moderate wind from the southwest, freezing level rises from 1200 m in the morning to 1800 m in the afternoon, alpine high temperatures around -3 C.

Avalanche Summary

A few small loose avalanches were observed on sun-exposed slopes on Tuesday, otherwise no notable avalanches were reported on Monday or Tuesday. Over the weekend a few small wind slab avalanches (see this MIN report) and size 2 cornice falls were reported. The cornice falls did not trigger any slabs on the slopes below.

Snowpack Summary

5-15 cm of new snow and strong wind will form isolated wind slabs in alpine terrain on Wednesday. A crust can be found near the surface up to 2000 m on solar aspects and up to 1700 m on all other aspects. Alpine terrain is heavily wind affected.

A thick rain crust that has facets associated with it sits 30-60 cm below the surface and can be found up to ridge top. We have only seen one avalanche on this layer since February 17th. The mid-pack is well settled and strong, but the base of the snowpack contains basal facets that are most prominent in shallow rocky start zones.

Terrain and Travel

  • Be carefull around freshly wind loaded features.
  • Large cornice falls are dangerous on their own.

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.