An EF 0 tornado was confirmed from the evening of June 22 in Holmesville, near Goderich. I believe it was the storm that had some night photos taken of it that looked a lot like a tornado but not for sure. Below is the release from EC:
Updated weather summary for Southern Ontario and the National Capital
Region issued by Environment Canada at 11:27 A.M. EDT Monday
13 July 2015.
Second tornado of the season added to the list
Environment Canada has continued to investigate the occurrence of a
possible tornado in the Holmesville area of Huron County that
occurred around 9:40 PM EDT on June 22. Holmesville is
Approximately 14 kilometres southeast of Goderich. There were storm
spotter reports of a possible tornado in this area at the time.
Subsequent investigation has shown that some minor building, tree
And vehicle damage occurred in the same area where the storm spotter
reports indicated the possible tornado.
An exact track of this event could not be determined. However, given
that the damage involved objects that were moved in different
directions and some dirt and leaf splatter was reported from this
event, it is likely it was caused by a tornado.
Given the relatively minor nature of the damage, this tornado has
been rated as an Enhanced Fujita scale zero (efzero) tornado with
peak winds between 90 and 130 kilometres per hour.
This now brings the total count of tornadoes in Ontario this year to
two. Ontario normally confirms 12 tornadoes each year in a season
that runs from late April until early October.
Please note that this summary may contain preliminary or unofficial
information and does not constitute a complete or final report.