Catamount Trail South from Nebraska Valley
Quick report
- Cracking
- specific
- Collapsing
- specific
We have a deep snowpack and the skiing is about as good as it gets. isolated low elevation, thin snowpack areas are harboring a weak faceted layer that is starting to become reactive and with additional load could become more active. New snow (2-4" of dense) overnight and still snowing. high winds (40+ mph) and blowing snow were present for the whole tour. poor snowpack structure was noted on many aspects at low elevation. this was noted through sandboxing while breaking trail and feeling the weak layer with pole probing. Cracking on new wind drifted snow was noted. a few isolated collapses (approximately 10-20' in diameter) with audible whumpfing and visible cracking were noted failing on the faceted layer on the ground. no rapid warming, though temps are forecasted to rise to the mid 30s this afternoon. For those counting that 4 out of 5 red flags. This morning at about 7:00 AM a member of a different party that I met up with on the skin track reported triggering, getting caught in and getting partially buried in a D1.5 R1 avalanche that broke on the faceted layer to the ground. Due to the nature of the slope, the skier who triggered the avalanche had to avoid getting pushed into a tree and was buried just past his waist and was able to self extract. He was unharmed. A few things to note about this avalanche and this PWL issue we are dealing with 1) even a small slide like this can have consequence, especially in more committing terrain. 2) If we get more load on this weak layer, I would expect the size and energy of the avalanches to increase. This could happen today wtih additional wind, or this weekend with the first high moisture storm we've had in over a month. 3) This instability is very real and present, however is it also isolated to lower elevation snowpacks that are/ were thinner in early January. If we do get a big wet storm this weekend, I am somewhat concerned about low elevation slopes that people generally would not consider having avalanche hazards presenting a real danger, this could even include stream banks and road cuts.
Weather
- Air Temp
- 23
- Cloud Cover
- overcast
- Wind Loading
- intense
- Recent Snowfall
- 10
- Snow Avail For Transport
- large amounts
high winds and lots of snow transport. temps were moderate (high teen and lower 20s). snowing at less than 1 cm/hr
Avalanche
- Size
- D1.5 R1
- Type
- SS
- Aspect
- NW
- Trigger
- AS
- Elevation
- 1700 ft
This avalanche was unintentionally trigger. the skier went for a short ride and had to work to keep from hitting a tree and was buried just past his waist and was able to self extract. A few things to note: 1) even a small slide like this can have consequence, especially in more committing terrain. 2) If we get more load on this weak layer, I would expect the size and energy of the avalanches to increase. 3) this instability is very real and present and also isolated to lower elevation thin snowpacks.