EF0 downburst at Udney ON on Sep 6

NTP investigation has resulted in the confirmation of an EF0 downburst at Udney, ON following the passage of a line of storms on September 6. Tree damage and minor structural damage were found. Given the damage dimensions are less than 4 km, the definition of a microburst is met.

Details are provided in the event summary below, along with images from the survey.

Note that there were a number of other locations in Central Ontario that had reports of treefall, some of which caused structural or power line damage. However, the tree damage appeared to be widely scattered and not associated with an identifiable downburst (or tornado). Many of the trees also had obvious rot.


Event Name: Udney, ON

Date: September 6, 2023

Time: 5:00 PM EDT (2100 UTC) 

Final Classification: Downburst (Microburst)

Final EF-Scale Rating: EF0

EF-Scale Damage Indicator / Degree of Damage: FR12/DOD-2

Location of worst damage: 44.6180N, 79.2088W

Description: Tree damage was reported in the Udney area after a storm passed through. No injuries were reported. An NTP ground and drone survey was completed on September 8, 2023, documenting the reported damage along with minor roof damage to a home and shed, with damage found over a SW-NE-oriented area approx. 3.5 km long and 1.9 km wide. Damage assessed as EF0 downburst (microburst), with an estimated max. wind speed of 125 km/h. Satellite imagery review is pending. Event time is radar estimated.


House with shingle damage on three sides of the roof (only one side showing) and tree damage in the vicinity.

NTP drone image showing round hay bales that were rolled to the northeast by the microburst winds.