Recalling the 2005 storm that brought tornadoes and major flooding to Ontario

Randi MannDigital Reporter

On this day in weather history, three tornadoes touched down in Ontario.

This Day In Weather History is a daily podcast by Chris Mei from The Weather Network, featuring stories about people, communities and events and how weather impacted them.


On Friday, August 19, 2005, three tornadoes hit Southern Ontario. The tornadoes hit areas near Milverton, Salem, and Stratford. The event dubbed the "Southern Ontario tornado outbreak of 2005" caused more than $500 million worth of damages. The storms also caused extensive flooding in Toronto and surrounding areas.

It started early on the 19th as a low-pressure system over Michigan with a cold front nearby. The same disturbance caused a tornado outbreak over Wisconsin the day before.

Toronto, Ontario - Courtesy TWN

Toronto, Ontario. Courtesy of TWN

The system caused widespread thunderstorms. The first one popped up near Stratford and spanned to Georgian Bay. The second storm was right behind, near the shores of Lake Huron. These storms formed into dozens of cells, two of them turning into tornadic supercells.

Content continues below
Flooding on DVP in Toronto, Ontario - Courtesy TWN

Flooding on DVP in Toronto, Ontario. Courtesy of TWN

The major storm called the "Toronto Supercell" spawned a tornado near Milverton. The next tornado touched down in Salem and travelled to Lake Belwood. The storm morphed and started to produce winds of 100 km/h, golf ball-sized hail, and extreme rain, which subsequently caused flooding.

The final severe storm developed near Stratford, spawning an F1 tornado with wind reaching 150 km/h.

Sinkhole in Vaughan, Ontario - Courtesy TWN

Sinkhole in Vaughan, Ontario. Courtesy of TWN

The twisters uprooted trees, destroyed homes, downed power lines, and threw vehicles. Around 10,000 people were left without power, but there weren't deaths or injuries reported.

When the storm came close to the Greater Toronto Area, a tornado warning was issued, but the storm changed its characteristics. Wind gusts of well over 100 km/h (62 mph) blew through this densely populated centre. It was accompanied by golf ball-sized hail and heavy rain, flooding many parts of the city.

Content continues below

A total of 103 millimetres (4.1 inches) of rain fell in one hour in North York, double the amount left in that area by Hurricane Hazel back in 1954. Thornhill, just north of Toronto, received a staggering 175 millimetres (7 inches) of rain in less than 1 hour.

A fourth tornado was reported in the City of Toronto city, but it was never confirmed by the Meteorological Service of Canada.

To learn more about the Southern Ontario tornado outbreak of 2005, listen to today's episode of "This Day In Weather History."

This Day In Weather History is a daily podcast by The Weather Network that features unique and informative stories from host Chris Mei.

Subscribe to 'This Day in Weather History': Apple Podcasts | Amazon Alexa | Google Assistant | Spotify | Google Podcasts | iHeartRadio | Overcast'

Thumbnail courtesy of TWN