Damage to buildings, trees and utility poles in Mitchell during intense thunderstorms last week was the result of a downburst.
Western University’s Northern Tornadoes Project (NTP) confirmed an EF1 downburst hit the area around 7 p.m. last Thursday. A survey team conducted a full ground and drone investigation in the two days that followed. They determined the downburst had an estimated maximum wind speed of 150 kilometres an hour, with intermittent damage found over an area approximately 13.4 kilometres long and up to 8.6 kilometres wide. A satellite imagery review is pending and the start time of the downburst was based on witness reports, NTP said.
A drive shed sustained the worst of the damage. However, several barns, utility poles, trees, and crops were also damaged. No injuries were reported.
The downburst, which is a powerful downdraft of air that spreads outward rapidly upon hitting the ground, hit as a line of severe thunderstorms barreled across midwestern Ontario. A large number of hydro poles were snapped along Highway 23 between Line 28 and Line 32, while a number of other roads were blocked by downed tree limbs and other debris. Power was knocked out to tens of thousands of Hydro One customers with many not reconnected until Friday afternoon.
An NTP survey team returned to midwestern Ontario on Sunday to investigate at least one confirmed tornado between Goderich and Bayfield. The twister reportedly hit roughly 15 minutes after Environment Canada issued a marine tornado warning along the Lake Huron shoreline around 6:45 p.m. on Saturday. Damage has been reported in the Holmesville area.
Additional damaged reports can be submitted to NTP through its website at uwo.ca/ntp or by emailing ntp@uwo.ca.