Eyewitnesses observed this tornado touching down and spinning debris in the air, but it did not cause any damage. This was one of two tornadoes to touch down in Southern Ontario on August 19, 2001. The other was an F0 at Wyndham Hills.
Figure 1 depicts the surface observations at 2:00 pm EDT, which shows a trough across southern Ontario, bringing southerly winds across the province. This trough, possibly aided by lake-breeze boundaries and the cold front, triggered thunderstorms across southern Ontario on August 19th, which ultimately resulted in two F0 tornadoes.

According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 4:17 pm EDT near Ipperwash, ON. The path and width of the tornado was not documented by ECCC. The tornado caused no fatalities, injuries or property damage.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 18Z Sun Aug 19 2001. Retrieved from: https://www.wpc.ncep.noaa.gov/archives/web_pages/sfc/sfc_archive.php
Environment and Climate Change Canada Data. (2018). Canadian National Tornado Database: Verified Events (1980-2009) – Public. Retrieved from: http://donnees.ec.gc.ca/data/weather/products/canadian-national-tornado-database-verified-events-1980-2009-public/