Environment Canada says a preliminary investigation shows that a tornado touched down in an area northwest of Toronto Thursday evening.

The national weather agency said the EFI tornado blew through Shelburne with winds between 135 to 175 km/h.

The roof of a barn about five kilometres northwest of the town was torn off and thrown about 150 metres. The side of another barn was trimmed off seven kilometres west of the small community.

Meanhwhile, in the Town of East Gwillimbury, police say about 20 hydro poles were knocked down on Woodbine Avenue between Green Lane and Garfield Wright Boulevard. York Regional Police say the area will be closed to traffic for the next two or three days.

According to Environment Canada, a cold front accompanied by precipitation is expected to cross southern Ontario on Friday, bringing with it westerly winds that are expected to persist for several hours.

With files from The Canadian Press