Figure 1 depicts the surface observations at 1:00 pm CDT, which shows a stationary front across Northeastern Manitoba and a trough of low pressure on the Saskatchewan/Manitoba border. This trough became the focus for thunderstorm activity in the early afternoon hours of July 4th, which ultimately led to this tornado.
According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 1:05 pm CDT near Swan River, MB. The path and width of the tornado was not documented by ECCC. No property damage was documented for this tornado.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 18Z Sat Jul 4 2009. 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/