Swan Range

An avalanche warning is in effect. Moderate to strong winds and new snow will increase the avalanche danger throughout the day. Avalanches failing in the new snow can step down to a much larger, deadly avalanche. Recent close calls and accidents of riders caught in large avalanches are an additional sign to stay off and out from underneath avalanche terrain today.

On Saturday we received three reports where riders had close calls or accidents. We are happy to report that no serious injuries were sustained in any of the cases. These slides all failed at roughly 6500’ and above. Aspects were west, south, and northeast. Here are the observations (avalanche accident, incident, near miss). These are lessons for us all and we thank the people involved for sharing their stories. We extend that thank you to everyone who is sharing observations. 

Snowpack: “Exceptionally dangerous” are the first words that come to mind. I recall riding around on January 13th just after the rain event froze the surface into a rock hard ice crust. I said out loud, “this is going to mess with us for the rest of the season.” The real insult was the few inches of snow that fell days after, followed by almost two weeks of no snow and cold temperatures. This snow sat on the surface and faceted and the conditions were ripe for making surface hoar. This is the weak layer that plagues our entire region. It is distributed and producing avalanches across all aspects, though most of them have occurred on north through east-facing slopes. Other than slab thickness and destructive potential, there is virtually no difference between the three ranges.

Weather: Yesterday temperatures rose almost ten degrees during the afternoon and evening hours. This climb in temperatures settled our cold snow by 2 inches in most places. These warm temperatures and fairly rapid settlement are perfect for building slabs. So, areas where the slab consisted of mostly faceted, cold snow, now may be ripe for human triggering. I have more of a concern today with elevations below 5800’ where most of the activity has been happening.

Today will be a warm, wet, and windy day. We can expect a range of 4 to 8 inches of new snow with the Flathead Range seeing the upper end of those totals. Winds are going to be blowing out of the southwest and will turn to a more westerly direction this evening. Yesterday I found about of foot of snow available to transport on west aspects. That along with new snow will continue to build thick, firm slabs that are capable of burying and injuring a rider.

A few reports came yesterday of a freezing rain event in the southern Whitefish Range. This will do one of two things. First, it will provide a smooth layer for snow to slide on. Second, it can help reduce the amount of snow available to transport since it is capping the snow surface. For decision-making today, expect new snow to bond poorly if you find a recent crust below the surface.

We will likely see rain at low elevations today. If this occurs, expect a round of loose wet avalanches. Surface snow will wet and slide easily on the 1/13 rain crust.

Terrain for today: There is no doubt that the hazard will increase throughout the day and into tonight. Avalanches have the ability to propagate wide and run far distances. Stay out from underneath avalanche terrain today and keep slopes below 30 degrees if you get above 5000’. If you decide to go out today, it would be a day to find low angled terrain with no threats from above. The other option if you are gluten for punishment, walk a ridgeline and feel the force of strong winds.