Figure 1 shows the surface observations at 7:00 am CDT, which shows an area of low pressure developing near the Montana/Saskatchewan border and a warm front in western North Dakota. A low would later develop and move northeast into northern Manitoba, dragging a cold front with it. The cold front became the focus for thunderstorms across western Manitoba in the afternoon and evening hours of August 14th, which ultimately led to this tornado.
According to Environment and Climate Change Canada (2018), an F0 tornado touched down at 7:00 pm CDT near Decker, MB. The track and width of this tornado was not documented by ECCC. The tornado caused no injuries, fatalities or property damage.
Sources
NOAA Central Library. (2020). U.S. Daily Weather Maps. Saturday August 14, 1982 [PDF]. Retrieved from https://library.noaa.gov/Collections/Digital-Collections/US-Daily-Weather-Maps
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/