An avalanche that fails in symphony with another adjacent avalanche.
The sympathetic avalanche fails because the crack propagation from the initial failure (either from a natural or artificial trigger) spreads to an adjacent start zone. With this type of failure, you can have multiple start zones release avalanches at approximately the same time.
![](https://avalanche.org/wp-content/uploads/2022/09/sympathetic-600x450.jpg)
Skier triggered (on the right) and sympathetic (on the left) avalanches released at approximately the same time. Credit: Crested Butte Avalanche Center.
![](https://avalanche.org/wp-content/uploads/2022/09/IMG_2132-1-600x400.jpg)
A pair of sympathetic avalanches that released in synchrony with a skier triggered avalanche. Credit: Crested Butte Avalanche Center