Environment Canada says one tornado touched down as wild weather swept across southern Ontario on Wednesday night.
An F1 tornado with winds between 120 and 170 kilometres an hour was confirmed southeast of Cambridge.
Environment Canada says the tornado touched down just after 9 PM at Little's Corners and tracked 15 kilometres southeast to Westover.
The path of the tornado was up to 300 metres wide at times, but little damage is reported.
There were also reports of tornadoes near Shelburne, Lucan and between St. Joseph and Bayfield -- but they did not prove true.
An investigator was also sent to the Burlington area to check whether damage there was caused by a tornado, but that event has been classified as a downburst.
There were also reports of possible tornadoes and funnel clouds in parts of eastern Lambton County, Middlesex County, Huron Perth and Bruce Counties.
Wednesday night's storm also produced high winds, lightning and torrential rain that left baseball size hail -- and the storm also knocked down tree branches.