Half an hour after the first EF0 tornado near Fergus, CANWARN spotter Dave Patrick captured a second EF0 tornado on video as it touched down west of Salem. This tornado was brief and did not cause any damage.

Figure 1 depicts the surface observations at 5:00 pm EDT, which shows a warm front across southern Ontario. This front became the focus for thunderstorm activity throughout the late-afternoon and evening hours of September 1st, which ultimately led to this tornado.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 21Z Sun Sep 1 2013. Retrieved from: https://www.wpc.ncep.noaa.gov/archives/web_pages/sfc/sfc_archive.php