Tornado near Sudbury ON on Aug 12

An NTP investigation has concluded that a tornado (over water) occurred with a thunderstorm near Sudbury, ON on August  12. The tornado was reported as a waterspout over Whitewater Lake at Azilda, ON and no damage was reported.The event was therefore assigned a default EF0 rating.

Details including a radar image are provided below. Event information can also be viewed and plotted via the NTP Dashboard at


Event Name: Whitewater Lake (Azilda), ON

Date: August 12, 2023

Event Start Time: 4:23 PM EDT (2023 UTC)

Final Classification: Tornado (Over Water)

Final EF-Scale Rating: EF0-Default

Estimated Tornado Location: 46.538N, 81.138W

Description: Witness captured video of a waterspout over Whitewater Lake near Azilda (Sudbury area). No damage reported.

Radar image showing the reflectivity and radial velocity data at the time of the event. Note a relatively weak velocity couplet over Azilda. However, this storm also rapidly developed over the area and was relatively brief. That is - more investigation needed to determine if the tornado developed by supercell or non-supercell processes.

A video of the tornado can be view on Facebook at