Strong Severe Risk Including Tornadoes Possible for Parts of Southern Ontario on Tuesday (June 29)

Forecast Discussion

There is a fairly strong risk for severe thunderstorms on Tuesday throughout parts of Southwestern, Central and Eastern Ontario along with the GTA. The first round of storms will come in the morning which should be mainly non-severe. There is a questionable morning severe risk along the Lake Huron shoreline with damaging wind gusts, moderate-sized hail and heavy rainfall.

The main story will come later in the day as several isolated storms are expected to pop up in a zone stretching from Lake Huron through Lake Simcoe just to the north of the GTA sometime during the afternoon. The environment is favourable for any storm that develops to quickly become severe with damaging wind gusts, large hail and heavy rainfall.

There is also the potential for one or two tornadoes with the strongest storms although it’s not guaranteed. The biggest tornado threat exists through Simcoe County and around the Lake Huron shoreline. Wouldn’t be out of the question to see a waterspout develop over Lake Huron or Georgian Bay and come on land somewhere in the above-mentioned region.

We’ll see the mature storms track eastward as they move into the GTA and through Eastern Ontario north of Lake Ontario during the late afternoon and early evening hours. The main threat later in the evening will be strong wind gusts as the tornado risk diminishes and the storms will fully move out of the region by the early overnight hours.