Figure 1 shows the surface observations at 7:00 pm CDT, which shows a cold front moving through Manitoba. This cold front became the focus for intense thunderstorms in the late afternoon and evening hours of July 3rd, which ultimately led to this tornado.
According to Environment and Climate Change Canada (2018), an F1 tornado touched down at 9:33 pm CDT near Mariapolis, MB. The track 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 00Z Fri Jul 4 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/