An F1 tornado touched down in Bowmanville yesterday, Environment Canada says.

The strong winds flipped the roof of one barn onto another adjacent property, collapsing a second barn. Though the foundation of the barn was completely destroyed, authorities said no one was injured.

On Tuesday, Environment Canada sent a team out to the area east of Toronto  to view the damage and assess whether it was indeed caused by a tornado.

Witnesses said they saw a funnel cloud in the Orono County area and reported several trees had come down. There was also a strong thunderstorm in the area at the time.

 F2 tornadoes hit Vaughan and Durham on August 20, destroying dozens of homes and killing a young boy just north of Durham in Grey County.

A total of 17 tornadoes struck in southern Ontario that day, Environment Canada said on Sept. 22. Four of them were F2 tornadoes.

The yearly total is now 27, including the Bowmanville tornado.

An average tornado year in Ontario is 11, with 2006 setting a record of 29. Tornadoes have been known to occur in southern Ontario into early November.