At about 4:30 pm, witnesses reported observing a funnel cloud touch down and destroy a barn. Debris from that structure was scattered and trees and power poles were also knocked down.
This was one of four tornadoes to touch down in Southern Ontario on June 25; the others:
Figure 1 depicts the surface observations at 2:00 pm EDT, which shows a cold front slicing through southern Ontario. This front became the focus for intense thunderstorms in the early afternoon hours of June 25th, which ultimately led to several tornadoes across Ontario.
According to Environment and Climate Change Canada (2018), an F1 tornado touched down at 4:30 pm near Leamington, ON. The tornado travelled for 150 metres, but the width 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 Thu Jun 25 2009. 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/