The Edmonton tornado of 1987, an event also known as Black Friday to Edmontonians, was a powerful and devastating tornado that ripped through the eastern parts of Edmonton, Alberta, Canada and parts of neighbouring Strathcona County on the afternoon of Friday, July 31, 1987. It was one of seven other tornadoes in central Alberta the same day.The tornado peaked at F4 on the Fujita scale and remained on the ground for an hour, cutting a swath of destruction 30.8 km (19.1 mi) in length and up to 1.3 km (0.81 mi) wide in some places. It killed 27 people, and injured more than 300, destroyed more than 300 homes, and caused more than C$332.27 million (equivalent to $665 million in 2020) in property damage at four major disaster sites. The loss of life, injuries and destruction of property made it the worst natural disaster in Alberta's recent history and one of the worst in Canada's history.

Weather forecasts issued during the morning and early afternoon of July 31, 1987 for Edmonton revealed a recognition by Environment Canada of a high potential for unusually severe thunderstorms that afternoon. Environment Canada responded swiftly upon receipt of the first report of a tornado touchdown from a resident of Leduc County which is immediately adjacent to Edmonton's southern boundary.