LONDON, ONT. -- A tornado warning is in effect for St. Thomas, Aylmer and Eastern Elgin County.

Environment Canada issued the warning shortly after 3 p.m. Thursday.

Meteorologists are tracking a severe thunderstorm that is possibly producing a tornado.

Damaging winds, large hail and locally intense rainfall are also possible.

The agency is warning that this is a potentially dangerous situation and are asking people to take cover if threatening weather approaches.