Forecaster Observation - Rescue Creek, Flathead Range

The focus of our tour was to assess avalanche type, size and distribution related to the recent warm wet weather.  We chose Rescue Creek in the Flathead Range due to its steep terrain, multiple aspects and numerous avalanche paths.

We observed approximately 8 loose wet avalanches that had occurred either Saturday or Sunday, March 5 or 6. These released on north-northwest aspects along with south-southeast aspects. We assumed that the rain that fell to 7000 feet on both of those days was the trigger to initiate these slides.  All of these avalanche appeared to involve only the surface snow and no evidence of these slides stepping down to a deeper layer was observed. We did not notice any cornice fall associated with these slides.

The avalanche destructive potential of these slides varied between D1 (relatively harmless to people) to D2 (could bury injure or kill a person). There was one slide that we classified as a D2.5. The size of these slides relative to their avalanche path was on the small size and were classified R1 and R2 with one being an R3.  Average vertical distance that the slides traveled was approximately 500+ feet. 

We also observed 3 older wet loose avalanches that had occurred over the past week or two. One of these slides was classified as a D3 (could bury and destroy a car, damage a truck, destroy a wood frame house, or break a few trees) and R3 (medium size, relative to path). These were on south-southeasterly aspects and were most likely triggered by sunshine and warming of the surface snow. 

Snowpack Observations: At 10:00 a.m. we traveled on a 4 inch thick knife hard surface crust at 4000 feet in the valley bottom.  By 10:40 the sun was breaking the crust down on an easterly aspect at 4400 feet.   

We observed 2 glide cracks that have formed on easterly aspects at approximately 6200 feet.