Avalanche forecast

Whitefish Range

Flathead Avalanche Center
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Avalanche danger

Wed
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

A hard crust and cold morning temperatures will reduce the chances of wet avalanche activity. Move to colder aspects IF you feel the surface snow become wet and unsupportable late in the day. Large avalanches failing deep in the snowpack have occurred this month in complex, rocky terrain above 6500 feet. Ride one at a time and give similar slopes a wide berth. 

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    Reported avalanche activity failing on persistent weak layers this month has occurred on easterly facing aspects. These avalanches have all failed above 6500 feet. Likely trigger points are areas where the snowpack is thin and weak. These include rocky outcroppings and wind-swept or scoured locations where the weak layer is buried closer to the surface. Identifying those areas is challenging at times. Hedge your bets by steering far away from rocky outcroppings and complex-looking terrain. Sticking to aspects that have not produced persistent slab avalanches is another way to reduce your chances of triggering a slide. Those aspects are due south-southwest-west. 

    (3/4/2023)

    A very large D3 hard slab avalanche on Nyack Mountain. Notice the rocky characteristics of this slope up near the ridge. This type of terrain is "complex." 

    Photo: md

Avalanche Discussion

Last night was the coldest night since March 16th. Temperatures at remote weather stations throughout the advisory dropped to 10-20 degrees F. Overnight temperatures froze the surface into a hard and supportable crust on sunny aspects. 

Today we can expect clear skies and warming temperatures. Freezing levels will reach roughly 6000 feet in elevation late this afternoon. In the past 24 hours, winds out of the east and north increased in speeds. This cold wind has very little snow available to transport. 

If you take advantage of the dry snow on north and east aspects, continue to be diligent about how you travel since buried weak layers still exist. Travel one at a time and give rocky, complex-looking terrain a wide berth. Reported avalanches on persistent weak layers this month have failed on east-facing slopes. Those avalanches occurred in the northern Whitefish Range, Glacier National Park, and just outside the advisory area in Glacier National Park. This pattern tells us those aspects are more susceptible to triggering. 

Throughout today, solar radiation and warming temperatures will soften the snow surface on sunny aspects throughout the day. Today's frozen surface may last late into the afternoon, providing a longer window of generally stable avalanche conditions. Keep an eye on west-facing slopes this afternoon as temperatures climb. Although the snow surface has been thoroughly worked over in the past week by melt-freeze cycles, the intense March sun could still produce some isolated avalanche activity. Steep, rocky slopes absorb the most heat and are common areas for point releases to start from. If you plan to be out late in the day, choose a route that minimizes overhead exposure to large avalanche terrain that faces west. 

Cornices are likely beginning to un-root themselves with warming temperatures. These are often referred to as “backcountry bombs” since they can tumble down and trigger larger avalanches below. The slopes below corniced ridgelines are slopes that harbor weak snow. These can fail spontaneously, but are more likely late in the day when temperatures are warm. 

Glide cracks or "brown frowns" have opened up across the forecast area. Few have released as avalanches so far this season. These often fail during times of intense warming. The only way to manage this avalanche problem is avoidance. Identify where these exist, and avoid dawdling below. 

FOFAC Event: March 30th, 2023– Whether you're chasing tan lines, big lines, or both, you'll learn something valuable from FAC Lead Forecaster Mark Dundas about spring avalanche problems, how they differ from winter problems, and how to manage them. We will also discuss current conditions and concerns (or lack thereof!) with our spring snowpack. Enjoy a cold brew from Bias Brewing and a scoop from Sweet Peaks Ice Cream.

The event is free and open to everyone. Begins at 6 pm.

Regions covered