A storm spotter for Environment Canada saw a funnel cloud over Chatham last night. 

It happened just after 10 p.m.

Geoff Coulson is a warning preparedness meteorologist and said there is no evidence it became a full-fledged tornado.

"This is something that we do see at this time of year. We are now fully into the summer severe weather season, in particular in southwestern Ontario," he said. "We do know that over the years the corridor from Windsor through Chatham up onto London and into Barrie is a very active corridor for thunderstorm activity. And some of those thunderstorms do have the ability to produce funnel clouds and tornadoes."

Coulson said 5 to 10 per cent of thunderstorms can produce significant damage.

Meanwhile, Windsor could break a heat record today.  

Environment Canada is forecasting a temperature of 34 C. The record was set in 1952 at 33.9 C.

Coulson said it's noteworthy that the 30-plus temperatures will stick around so long.

"Right through the next six-seven days, the forecast is mentioning that each day we're expecting temperatures to get up in the low 30s; not necessarily every day with high humidexes of 40 C or more, but again a lot of heat expected," he said. 

Coulson says the normal high for this time of year is 27 C.