Environment Canada has reclassified a funnel cloud spotted earlier this week in Millbank, Ont., as a tornado.
Initial evidence and eyewitness reports did not immediately indicate the funnel cloud, which was seen on Sunday north of Cambridge, had made contact with the ground, said Geoff Coulson, a warning preparedness meteorologist at Environment Canada.
“For it to be a tornado, the visible funnel doesn’t need to come all the way to the surface, but there does need to be some evidence of contact with the surface, either in the form of swirling dust or debris,” he said.
In the next two days, they heard more reports from eye witnesses confirming the storm had been a tornado. It has now been rated an EF0 tornado, meaning wind speeds hit at least 90 km/h. No damage has been reported.
“There were actually eyewitnesses that saw beneath the surface of the funnel cloud,” he said.
“One of the eyewitnesses, who had a good vantage point under the funnel cloud itself, actually did see evidence of swirling dust and debris right at the ground level.”
In cases such as in Millbank when no additional evidence can be gathered regarding a tornado’s wind speed and no property damage has taken place, Environment Canada generally classifies them as EF0 – the lowest the scale has, Coulson said.
“From what we’ve been able to ascertain from the people that saw it, it was likely only a tornado very briefly,” he said. “It was in a relatively open area and so fortunately there was no damage that occurred that we’re aware of.”
However, the Millbank tornado brings the provincial tornado tally up to 12 for the 2014 season, which normally lasts from late April to early October. The average number of tornadoes per year in the province is 12.
“If we do see more of these events in August and September, it would likely be a little bit more-active-than-normal season,” he said.
Looking ahead to the long weekend, Coulson said southwestern and south-central Ontario can expect a mix of sun and clouds, with some isolated shower activity and the possibility of some thunderstorms.