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

Feb 28th, 2022–Mar 1st, 2022

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

Regions

Lizard-Flathead.

Still stormy!

Heavy rain and snow overnight will continue to keep avalanche danger elevated. Even as snowfall rates taper on Tuesday, the snowpack will need time to adjust to the new load. 

Travel in avalanche terrain is not recommended and stay clear of runout zones.

Confidence

High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

Monday night: Ongoing heavy precipitation with 20-40 mm, moderate southwest wind, freezing levels rising to 1900-2000 m and treeline temps hovering around zero.

Tuesday: Precipitation continues with 10-20 mm, moderate to strong southwest wind, freezing levels hovering around 1900-2000 m and treeline temperatures around 2 degrees. 

Wednesday: Flurries possible 5-10 cm, light to moderate southwest wind, some overnight recovery is possible, but freezing could still rise to about 1700 m during the day.

Thursday: Overcast with flurries, light southwest wind. Good overnight recovery but freezing levels rising during the day.

Avalanche Summary

Visibility was poor but numerous size 2 avalanches were reported from operators in the Lizard Range on Monday.

Snowpack Summary

By Tuesday morning there could be over 60-70 cm (depending on your location in the region) of new snow forming slabs over a variety of old surfaces like old wind affected snow, sun crusts, and cold weak crystals on shaded aspects. Rain will likely soak new snow overnight on Monday night at treeline and below treeline elevations.

Storm slabs or loose wet avalanches may step down to old persistent layers such as the surface hoar layer buried at the end of January. The distribution of this layer is spotty in nature but has produced avalanches and snowpack test results in the past week, mostly in the Flathead. While it does not appear to be as widespread or reactive in the Lizard Range, it has been found in some locations. 

The lower snowpack is well consolidated, with a crust/facet layer from early-December found near the bottom of the snowpack. It is currently considered dormant but with big rain on snow events, operators will be on guard. Check out the forecaster blog for more information. 

Terrain and Travel

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.

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.

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.

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.