It is possible that as many as four tornadoes touched down across southwestern Ontario as severe storms tore through the region on Sunday.
Western University's Northern Tornadoes Project has sent teams to investigate damage south and east of London in Belmont and Beachville and north and west of London in Exeter and Grand Bend.
"There are a number of indications on doppler radar [Sunday] of areas of tight rotation when that big area of storms moved through and we are finding that all of the damage that we have been getting reports about are located under where those bits of tight rotation were. It is possible these were tornadoes along that leading edge of the thunderstorm," said Dr. David Sills, executive director of the Northern Tornadoes Project.
One of the teams' areas of focus will be in Belmont where trees were downed, a roof damaged and a camper trailer tossed into the side of a house. An EF-1 tornado previously tore through Belmont on June 10. It travelled a distance of 18 kilometres and had a maximum width of 250 metres. The twister snapped hydro poles, downed tree limbs, and damaged buildings, but did not lead to any injuries.
In the thick of Sunday’s storms, tornado warnings were issued across the region. Winds gusting up to 100 km/h saw trees downed in London, Lucan, Beachville, Mitchell, and Lambton. Farm buildings and silos were damaged in Exeter and Woodstock.
A waterspout was sighted north of Sarnia over Lake Huron, according to officials with Environment Canada.
The storms became so intense there were also reports of flooding and near-zero visibility in torrential downpours.
Over 37,000 Hydro One customers were left without power for several hours. Those in the hardest-hit areas across southwestern and central Ontario remained without hydro Monday morning.
No injuries associated with the wild weather have been reported.
Sills believes any tornadoes that are confirmed to have touched down on Sunday will be on the lower end of the Enhanced Fujita (EF) Scale.
"Most of these are EF-0 or EF-1 as far as we can tell. It is mostly tree damage for these," said Sills. "If it is an EF-0 it is wind speeds of 90 to 130 km/h. If it is an EF-1 it is wind speeds of 135 to 175 km/h... The tornado that went between Lucan and Exeter has some more significant damage and that could get up to EF-2, we will have to see what the results are."
EF-2s produce winds between 180 to 220 km/h.
So far this year, there have been 14 confirmed tornadoes in Ontario, seven of which were in southwestern Ontario. Prior to the launch of the Northern Tornadoes Project the average number of verified tornadoes in Ontario each year was only 12. However, that doesn't mean we are seeing more tornadoes, cautioned Sills.
"We have started doing much more thorough investigations and following up on things that normally wouldn't have been followed up on in the past, just because it takes so much time," said Sills. "So we are getting higher tornado numbers in the last few years just because we are putting in that extra effort to find them... The numbers are getting high but it is not necessarily because more tornadoes are occurring."
The Northern Tornadoes Project has confirmed a storm that rolled through the region on Thursday led to a tornado in the Brantford-area. Investigators made the determination based on photos, video and witness descriptions. With no significant damage associated with the twister, it has been given a preliminary rating of an EF-0.
Narrow area of wind damage in Belmont, ON, south of London. Shingles removed, trailer moved into house, trees and branches down. Witnesses describe debris whirling in the air (while raining). Possible tornado. #ONStorm pic.twitter.com/uyfhkvo5wc
— Dave Sills (@dave_sills) July 19, 2020