In this study, an analysis of static and dynamic arc in sphere gaps and leaning tree is carried out. A Stockwell Transform (ST) or S-Transform-based approach is used for the detection and classification of the high-impedance arc signals. Conductance variations in this scenario are also observed for various voltage levels and sphere gap length for different arc. The findings obtained by applying the ST technique to arc voltage signals effectively identify and distinguish the high-impedance arc based on their frequency signatures due to leaning tree from sphere gap arc. © 2021, Springer Nature Singapore Pte Ltd.