Environment Canada confirms that a tornado touched down near Stayner, west of Barrie on Monday.

The weather agency says damage caused by the tornado includes uprooted trees and an overturned trailer.

The strength of the tornado is still to be determined.

Damage in nearby communities -- including Collingwood, where a roof was removed from an industrial building -- is still being investigated.

The agency says Ontario has seen 11 tornadoes so far this year.