Supercell Tornadogenesis over Complex Terrain: The Great Barrington, Massachusetts, Tornado on 29 May 1995

The process of tornadogenesis in complex terrain environments has received relatively little research attention to date. Here, an analysis is presented of a long-lived supercell that became tornadic over complex terrain in association with the Great Barrington, Massachusetts (GBR), F3 tornado of 29 May 1995. The GBR tornado left an almost continuous 50–1000-m-wide damage path that stretched for ∼50 km. The apparent rarity of significant tornadogenesis in rough terrain from a supercell well documented in operational Doppler radar motivated this case study. Doppler radar observations showed that the GBR supercell possessed a midlevel mesocyclone well prior to tornadogenesis and that the mesocyclone intensified as it crossed the eastern edge of New York’s Catskill Mountains and entered the Hudson Valley. Tornadogenesis occurred as the GBR mesocyclone crossed the Hudson Valley and ascended the highlands to the east. Subsequently, the mesocyclone weakened as it approached the Taconic Range in western ...