Lizard Range and Flathead Avalanche Forecast

Issued: Apr 23rd, 2021 4:00PM

Sat Apr 24th Current Conditions
Alpine Moderate Treeline Moderate Below Treeline Low
Sun Apr 25th 2 Day Outlook
Alpine Considerable Treeline Moderate Below Treeline Moderate
Mon Apr 26th 3 Day Outlook
Alpine Considerable Treeline Considerable Below Treeline Moderate

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

This is the final forecast of the season! Forecast snow over the weekend may form reactive storm slabs; especially in wind affected terrain. Use small slopes with low consequence to test the bond of the new snow and avoid wind loaded slopes.

Summary

Confidence

Low - Forecast snowfall amounts are uncertain.

Weather Forecast

  

FRIDAY NIGHT: Snow; 5-10 cm. / Light, west ridgetop wind / alpine low temperature -5 / Freezing level valley bottom.

SATURDAY: Snow; 5-15 cm. / Light, southwest ridgetop wind / alpine high temperature -1 / Freezing level 1500 m.

SUNDAY: Snow; 10-20 cm. and another 5-10 cm. overnight / Moderate, southwest ridgetop wind / alpine high temperature 0 / Freezing level 1800 m.

MONDAY: Mostly cloudy / Light, west ridgetop wind / alpine high temperature 2 / Freezing level 2000 m.

Avalanche Summary

No avalanches were reported in this region on Thursday. 

Forecast snow over the weekend may form reactive storm slabs; especially in wind affected terrain. Wet loose avalanches are not expected over the weekend but will likely occur on Monday if the sun comes out.

NOTE: Observations are very limited during this time of year.

Snowpack Summary

10 cm of flurries and strong southeasterly winds on Thursday formed small wind slabs sitting on hard crusts on lee features below ridgetops. Forecast snow over the weekend may form larger reactive storm slabs; especially in wind affected terrain. The recent snow is sitting on a hard crust formed by the recent warm weather. 

Large cornices hang like Gargoyles over alpine ridgetops. Cornice falls can trigger large avalanches on slopes below that a single rider may not trigger.

The snowpack is overall strong and settled in most areas. However, steep and rocky alpine slopes with a shallow or thin to thick snowpack may still harbor deeply buried weak layers. Glide cracks releasing as full depth glide slab avalanches become more common in the spring and are extremely difficult to predict. Best practice is to avoid slopes with glide cracks.

The snow line is slowly creeping up the mountains, making some access areas snow-free. 

Terrain and Travel

  • Stay off recently wind loaded slopes until they have had a chance to stabilize.
  • Use small low consequence slopes to test the bond of the new snow.
  • Closely monitor how the new snow is bonding to the crust.
  • Even a small avalanche can be harmful if it pushes you into an obstacle or a terrain trap.
  • Caution around slopes that are exposed to cornices overhead.

Problems

Storm Slabs

An icon showing Storm Slabs

Likelihood

Possible-Likely

Expected Size

1 - 2

Forecast snow over the weekend may form reactive storm slabs; especially in wind affected terrain.

Aspects:

All aspects.

Elevations:

Alpine, Treeline.

Valid until: Apr 26th, 2021 4:00PM

Forecast Trend

The latest forecast danger ratings, broken down to elevation. See how an elevation is trending.