1985 Barrie Tornado Outbreak - The Grand Valley To Tottenham Supercell

The Grand Valley To Tottenham Supercell

The storm which had initially developed east of Clinton produced a new tornado a couple kilometres north of Arthur by 4:15pm. Many power lines and hydro towers were destroyed early in its lifetime (including those used to deliver electricity from the Bruce Nuclear Generating Station to northern and western parts of the Greater Toronto Area). The tornado quickly widened, intensified and reached violent proportions by the time it reached the small crossroads community of Grand Valley just before 4:30pm. At that point the tornado's damage path was approximately 200 metres (660 ft) wide.

The tornado caused major damage in the small town, where two people were killed. An elderly woman visiting from Scotland died as the home was destroyed, and a man was killed in his pickup truck on a nearby farm (Bruineman, 2010). The worst damage was found along Amaranth Street (running west to east, parallel to the tornado's path) where the local library, three churches, and many other homes were severely damaged or destroyed. Approximately sixty structures in total sustained damage. The most severe was on the north side of the street, where some homes exhibited classic F4 damage. The library roof was found some 200 metres away on a nearby house (Bruineman, 2010).

Continuing eastward through more open country, it brushed the northern outskirts of Orangeville about fifteen minutes later (Grazulis, 2001) where the southern portion of the Mono Shopping Plaza completely collapsed (injuring 67 people, one of them seriously). It then caused extensive damage to approximately fifty buildings (many of which were only recently built) about 2 kilometres (1.2 mi) south of the town of Tottenham at around 5:00pm. Two more people died here, as an elderly man was crushed under an equipment shed on his farm and a woman was killed in her home (Bruineman, 2010). The tornado continued moving to the east-northeast, crossing Highway 400 into York region. It just missed the cities of Newmarket and Bradford before lifting west of Mount Albert at 5:25pm, with a path length in excess of 100 kilometres (62 mi), thus becoming a Canadian record that still stands today. When the earliest tornado track maps were published within the next year, they showed this particular tornado to have tracked almost twice as far towards the Peterborough area before dissipating. In more recent years this theory has proved to be incorrect; it is likely that this supercell was also a cyclic one. See the section below.