Figure 1 depicts the surface observations at 7:00 am EST, which shows a low pressure system across Southern Alberta with a stationary front extending across Northern Saskatchewan and a cold front extending south across Western Montana. The interaction between the occluding front and the Rocky Mountains triggered thunderstorms across Central Alberta, which ultimately led to an outbreak of tornadoes on this day.
There were 10 other tornadoes on this day:
- Rocky Rapids, AB F1 Tornado
- Lake Wabamun, AB F1 Tornado
- Stony Plain, AB F1 Tornado
- Busby, AB F1 Tornado
- Lesser Slave Lake, AB F0 Tornado
- Abee, AB F1 Tornado
- Big Coulee, AB F3 Tornado
- Baptiste Lake, AB F0 Tornado
- Foremost, AB F1 Tornado
- Minburn – Myrnam, AB F1 Tornado
According to Environment and Climate Change Canada (2018), an F2 tornado touched down at 4:40 pm MDT near Dapp, AB. The path and width of the tornado was not documented by ECCC. No property damage was documented for this tornado.
NOAA Central Library. (2019). U.S. Daily Weather Maps. Friday June 29, 1984 [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/