Figure 1 shows the surface observations at 4:00 am CDT, which shows an occluding low pressure system over Alberta with an extending cold front on the Saskatchewan/Manitoba border and a warm front extending east into central Manitoba. Figure 2 also shows the advancing cold front across south-central Manitoba at 1:00 pm CDT. While Environment Canada did not document the date/time of this tornado,we believe that the cold front on this day spawned multiple tornadoes across southern Manitoba.
Other tornadoes that occurred on this day:
According to Environment and Climate Change Canada (2018), an F1 tornado touched down near St. Laurent, MB. The track, width, time and date of the tornado was not documented by ECCC. The tornado caused no fatalities, injuries or property damage. Only the month and start lat/lon were documented by ECCC.
NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 09Z and 18Z Thu Aug 3 1989. 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/