Tornadoes in Ontario

Environment and Climate Change Canada verified tornadoes for the thirty years from 1980 to 2009 and has not extended that database. Nothing here after 2009 is missing because Canada stopped having tornadoes: the modern Canadian record is kept by Western University’s Northern Tornadoes Project, which has surveyed every year since 2017 and confirms more tornadoes a year than this database averages, because it goes looking with satellite imagery and drones rather than waiting for a report.

We do not carry it. The Northern Tornadoes Project publishes its data under a Creative Commons Attribution-NonCommercial licence, which forbids use on a commercial site, and this is one. For the years from 2017 on, go to the project’s own open data.

Every tornado in this record is rated on Ted Fujita’s F scale, which rates the damage and reads a wind speed off it. Canada moved to the Enhanced Fujita scale on 1 April 2013, four years after this record ends, so no EF rating appears here at all. Wind speeds are the F scale as Environment and Climate Change Canada publishes it, rounded to 10 km/h.

1. F060 to 110 km/h

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. F1120 to 170 km/h

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. F2180 to 240 km/h

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, large trees snapped or uprooted, cars lifted off the ground.

4. F3250 to 320 km/h

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. F4330 to 410 km/h

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. F5420 to 510 km/h

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because nothing it passed carried a rating the scale can be read from.

1. F4, Barrie, OntarioMay 31, 19858 killed, 155 injured
2. F4, Grand Valley to Tottenham, OntarioMay 31, 19854 killed, 69 injured
3. F2, Near Ear Falls / Lac Seul, OntarioJuly 9, 20093 killed, 5 injured
4. F2, Durham, OntarioAugust 20, 20091 killed
5. F2, Bridgenorth, OntarioJuly 15, 19951 killed
6. F2, Norwich Township, OntarioAugust 12, 19901 killed, 2 injured

1. F4, Grand Valley to Tottenham, OntarioMay 31, 1985F4, 115.0 km (71.5 mi)
2. F4, Reeces Corners, OntarioMay 2, 1983F4, 30.0 km (18.6 mi)
3. F4, Barrie, OntarioMay 31, 1985F4, 15.0 km (9.3 mi)
4. F3, Arthur to Violet Hill, OntarioApril 20, 1996F3, 63.0 km (39.1 mi)
5. F3, Williamsford, OntarioApril 20, 1996F3, 37.0 km (23.0 mi)
6. F3, Alma to Hillsburgh, OntarioMay 31, 1985F3, 33.7 km (20.9 mi)
7. F3, Corbetton, OntarioMay 31, 1985F3, 20.4 km (12.7 mi)
8. F3, Frome to Port Stanley, OntarioAugust 28, 1990F3, 13.0 km (8.1 mi)
9. F2, Brady Lake to Maynooth, OntarioJune 16, 1986F2, 76.7 km (47.7 mi)
10. F2, Near Ear Falls / Lac Seul, OntarioJuly 9, 2009F2, 53.1 km (33.0 mi)

Warnings in force in Canada nowThe forecast in OntarioThe live radar over Ontario

Ratings are the survey’s, read off the damage rather than measured, on the Fujita scale as Environment and Climate Change Canada publishes it. Path length, width, time, casualties and cost are blank in the source for many tornadoes, and a blank here is a blank there rather than a zero. The rating scale is above.

Contains information licensed under the Open Government Licence - Canada.Source: Environment and Climate Change Canada, Canadian National Tornado Database: Verified Events (1980-2009).The tables, totals, rankings and wording on this page are WeatherOverTime’s, built from that database.