Figure 1 depicts the surface observations at 1:00 pm CDT, which shows a low pressure system on the Manitoba/North Dakota border with a cold front extending west across Manitoba and a stationary front extending east across northwestern Ontario. The interaction between these fronts and the low pressure led to three tornadoes across southern Manitoba on this day:

According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 3:15 pm CDT near Reinfeld, MB. The path and width of the tornado was not documented by ECCC. The tornado caused no fatalities, injuries or documented property damage.
Sources
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 18Z Mon Jul 14 2003. 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/