EF1 Downburst at Thedford, ON
An NTP investigation has concluded that damage south of Thedford, ON on July 20th was caused by a downburst in the rear-flank downdraft area of a supercell thunderstorm. A funnel cloud associated with a non-tornadic vortex aloft was also observed with the rotating updraft, just north of the area of damage. They occurred concurrently. Details are provided in the event summaries below.
Event Name: Thedford, ON (Downburst)
Date: July 20, 2022
Time: 6:40 PM CDT (2240 UTC)
Final Classification: Downburst (concurrent - primary)
Final EF-Scale Rating: EF1
EF-Scale Damage Indicator / Degree of Damage: SBO/DOD-8
Location of worst damage: 43.1155N, 81.8567W
Description: Structural and tree damage was reported south of Thedford after a storm passed through the area. No injuries were reported. An NTP ground survey was completed on July 21, 2022. Damage assessed as EF1 downburst, with an estimated max. wind speed of 150 km/h, with weak damage in multiple locations over an area at least 6.5 km long and 3.8 km wide. Satellite imagery review is pending. A concurrent vortex-funnel cloud aloft (NTV/VFCA) was also observed in the vicinity by witnesses.
One of several farm outbuildings damaged and destroyed by the downburst.
Event Name: Thedford, ON (NTV/VFCA)
Date: July 20, 2022
Time: 6:42 PM CDT (2242 UTC)
Final Classification: Non-tornadic vortex (vortex-funnel cloud aloft, concurrent - secondary)
Estimated event location: 43.137N, 81.883W
Description: Witnesses observed a funnel cloud associated with a non-tornadic vortex aloft southwest of Thedford. Damage was reported further south, attributed to a EF1 downburst assessed after an NTP ground and drone survey was completed on July 21, 2022.
