On Friday, May 31, 1985, a short-lived, but devastating, violent F4 tornado affected the City of Barrie, Ontario, Canada. The tornado was part of a larger outbreak that spanned both the preceding and the following day. The outbreak spawned several long-lived, cyclic, tornado-producing supercells over portions of Eastern Canada and the Great Lakes region of the Midwestern and Northeastern United States, one of which eventually generated the Barrie tornado.