Tornado in Ayr, Ont., classified as an upper level EF1

An investigation from Western University’s Northern Tornadoes Project has classified Saturday’s tornado in Ayr, Ont., as an EF1.

“Sometimes we go into a situation like that where we’re not sure if it was a tornado or not, it might have been a down burst, so in that case we’re looking for evidence about a long, narrow damage path. With this event, there were lots of videos and photos. So we knew we were looking at a tornado even before we got there,” David Sills, Executive Director of the Northern Tornadoes Project told CTV News Kitchener during an interview on Sunday afternoon.

Once Sills’ team arrived, investigation included ground and drone surveys of the tornado’s path and the heavily damaged area in the Greenfield Drive and Northumberland Street area.

In a news release, the organization said, “The tornado caused structural, vehicle and tree damage - with a preliminary rating of EF1 - along a narrow path over 5 km in length. Empty rail cars and a tractor-trailer were overturned, and two trailers were tossed.”

Ground photo showing empty railcars overturned and a large grain loader arm thrown across them. (Courtesy: Northern Tornadoes Project)

Sills said his team will continue to investigate what happened, and the classification of the tornado could still change as more information becomes available.

“We’ll look to see if there’s anything, any data, to show that it should go higher. Because there was some pretty impressive damage. Things like rail cars being blown over and trees that were basically scattered every which way, including against the direction of the tornado which is not typically common for a weak tornado.”

Sills added this tornado would be considered a particularly strong EF1 tornado.

“This is upper end EF1, almost to EF2. Some of the damage we did see was pretty impressive. The roof on the Home Hardware – the back part of it was mostly off. One wall was collapsed. Those train cars that were tipped over. There was one trailer that was actually lofted in the air and thrown on its top.”

Survey map showing the track of the tornado toward the ENE as well as the locations of ground and drone photos taken during the survey. (Courtesy: Northern Tornadoes Project)

The release said videos and photos show the tornado developed near Wolverton and tracked eastward toward Ayr.

The survey team believes the tornado had a maximum wind speed of 165 km/h and a track length of 5.23 km with a maximum path width of 230 metres.

Sills said the investigators believe the tornado lasted less than 20 minutes.

“That’s what makes it so very hard to warn for. The target lead time for a tornado warning is only ten minutes. Meaning that they’re trying to get a warning ahead of the tornado by only 10 minutes, because that’s how quickly they tend to form.”

No injuries were reported following the storm.

How tornadoes are classified

Sills said when it come to classifying a tornado, experts use what is known as the Enhanced Fujita Scale, commonly known as the EF Scale.

“The Enhanced Fujita Scale is a scale that goes from 0 to 5. What we do is look at the damage that is in front of us. Say, it’s a house – on the EF Scale we’ve got a damage indicator saying ‘house.’ Then it’s got a bunch of different degrees of damage associated with that house. We just find the one that matches the best,” Sills explained.

“Yesterday, as far as houses go, we found one house that had some roof covering removed, the shingles removed, and some structural damage. So that gets us to Degree of Damage 4. Then you go across and it’ll give you the range of wind speeds that’s usually associated with that. You’re looking for a maximum wind speed associated with each damage indicator you find, and then along the entire track of the tornado you take the maximum one, so the strongest wind speed, and that fits into the Enhanced Fujita Scale.”

Sills said an EF1 tornado has a wind speed ranging from 135 km/h to 175 km/h. He believes the tornado in Ayr had a maximum wind speed of 165 km/h.

Sills said he is surprised there hasn’t been a tornado across Canada that’s caused more damage in an urban area so far this year.

“Typically we get a number of EF2 tornadoes across the country. And this year we haven’t so far. We’ve only had EF2 tornadoes way up in the boreal forest.”

If anyone has video or photos they believe investigators should see, they can email the Northern Tornadoes Project.

Cleanup continues

The cleanup continues along Greenfield Road Sunday.

Crews were still on scene as of 10:30 a.m., removing downed trees and working on damaged hydro lines.

A security truck was parked in the Home Hardware parking lot after the building sustained heavy damage, including a partially torn off roof.

The Township of North Dumfries encourages impacted residents to visit AlertWR.ca for a checklist of what to do after an emergency.