Little is known about this F1 tornado that occurred to the northeast of Thunder Bay at Foam Lake. It was one of the only recorded tornado in the province of Ontario in 1987, making it one of the quietest years on record.
Figure 1 depicts a stationary front situated right over Hornepayne at 8:00 pm EDT (roughly 25mins after the tornado). A cumulonimbus was noted at this time on surface maps (Figure 1). This frontal boundary was responsible for initiating the storm that formed the F1 tornado in Hornepayne.
According to Environment and Climate Change Canada (2018), an F1 tornado touched down at 7:35 pm EDT in Hornepayne, ON and travelled for 400 metres. The tornado caused no injuries, fatalities or property damage.
Source
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/
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 00Z Thu Jul 23 1987. Retrieved from: https://www.wpc.ncep.noaa.gov/archives/web_pages/sfc/sfc_archive.php