Lizard Range and Flathead Avalanche Forecast

Mar 24th, 2020 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs.

Forecast confidence is low due to a lack of field observations. New and reactive wind slabs should be expected in higher elevation terrain.

Summary

Confidence

Low - Uncertainty is due to the limited number of field observations.

Weather Forecast

Tuesday night: Cloudy with continuing isolated flurries and a trace of new snow. Light to moderate southwest winds.

Wednesday: A mix of sun and cloud with isolated flurries and a further trace of new snow. Light to moderate west winds. Alpine high temperatures around -7.

Thursday: Sunny. Light to moderate southwest winds. Alpine high temperatures around -6.

Friday: Mainly cloudy. Light to moderate southwest winds. Alpine high temperatures around -5.

Avalanche Summary

No new avalanches were observed from limited reports on Monday and Tuesday. 

Looking forward, wind slab activity may increase as continuing snowfall and elevated winds form fresh slabs.

Snowpack Summary

Continuing light snowfall and elevated southwest wind are expected to form new wind slabs in exposed terrain. The new snow will sit on a melt-freeze crust on sun-exposed slopes or on previously wind-affected snow, so new slabs may take some time to bond to the snowpack.

A layer of faceted grains overly a melt-freeze crust from early February. This layer currently sits 30 to 60 cm below the surface. This layer remains dormant and has not produced a reported avalanche for about a week.

The base of the snowpack may contain a weak layer of faceted grains that are most prominent in shallow rocky start zones with a snowpack depth of 150 cm or less.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Make conservative terrain choices and avoid overhead hazard.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible-Likely

Expected Size

1 - 2

Wind slabs are expected to form as light snowfall continues with elevated west and/or southwest wind. Increase your caution in exposed terrain, particularly in lee slopes near ridges.

Aspects:

North, North East, East, South East, South, North West.

Elevations:

Alpine, Treeline.

Valid until: Mar 25th, 2020 5:00PM