Figure 1 shows the surface observations at 4:00 pm CDT, which shows a low pressure in northern Manitoba with a cold front extending south into southeast Saskatchewan. The cold front was the focus for thunderstorms across southern Manitoba in the afternoon hours of August 19th, which ultimately led to this tornado.
According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 6:50 pm CDT north of Stockton, MB. The track and width of the tornado was not documented by ECCC. The tornado caused no fatalities, injuries or property damage.
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 21Z Tue Aug 19 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/