Passive radar avalanche warning method and system

The present disclosure relates to a passive bi- or multi-static radar avalanche warning concept. An area (120) of a potential avalanche is illuminated with at least one third-party transmitter (110). A first signal (115-1) corresponding to a direct arrival from the third-party transmitter (110) and a second signal (115-2) corresponding to a reflection from the area (120) of the potential avalanche are obtained. A Doppler shift between the first and the second signal (115-1; 115-2) is determined. An avalanche is indicated if the Doppler shift exceeds a predetermined threshold.