Figure 1 depicts the surface observations at 12:00 pm MDT. There were four tornadoes on this day, the others being:

According to Environment and Climate Change Canada (2018), an F2 tornado touched down at 8:30 pm MDT in Provost AB. The path and width of the tornado was not documented by ECCC. The tornado caused $100 thousand dollars in property damage.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 18Z Wed Jun 18 1986. 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/