Figure 1 shows the surface observations at 1:00 pm CDT, which shows an occluding low pressure system on the North Dakota/South Dakota border with an occluded front just south of the Manitoba border. This front was the focus for thunderstorm activity in southern Manitoba, which ultimately led to this tornado.
According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 11:35 am CDT near Winkler, MB. The path 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 18Z Sun Jun 6 1999. 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/