Aug 20 2014
Weak tornado caught on camera by local residents as it touches down near Erin
This EF0 tornado touched down near Erin at around 6:30pm and was captured in photos and on video by area residents. Witness videos showed a whispy tube, fully condensed to the ground, exhibiting slow but clear rotation as it churned in area fields. No damage was caused.
— The Weather Network (@weathernetwork) August 21, 2014
— JODY TEETER (@teetertauter) August 21, 2014
By definition the winds of a tornado must be associated with a cumuliform cloud, in contact with the ground and violently rotating.
Even though there were many photos and videos that showed the fully condensed funnel touching the ground, the extremely slow and weak rotation made it initially unclear to Environment Canada officials as to whether all criteria – namely, violent rotation – for tornado classification were being met. However, video and radar analysis led investigators to eventually conclude that they were, and this was indeed an EF0 tornado.