Winthrop, ON F1 Tornado of May 22, 2004

Huron - Perth

At Winthrop, a farm sustained extensive damage. Trees were snapped and uprooted and a large shed was destroyed and scattered across the property; the farm house was struck by this and other debris, shattering windows and destroying its roof.

Figure 1 depicts the surface observations at 5:00 pm EDT, which shows a stationary front across southern Ontario. This front became the focus for intense thunderstorms across southern Ontario, which ultimately resulted in two F2 tornadoes, one F1 tornado and one F0 tornado.

Figure 1. Surface analysis at 21Z on May 22, 2004 showing mean sea-level pressure (MSLP) contours, surface observations, fronts and pressure centres (WPC, 2017)

According to Environment and Climate Change Canada (2018), an F1 tornado touched down near Winthrop, ON. The path and width of the tornado was not documented by ECCC. The tornado caused no fatalities, injuries or property damage.


NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 21Z Sat May 22 2004. Retrieved from:

Environment and Climate Change Canada Data. (2018). Canadian National Tornado Database: Verified Events (1980-2009) – Public. Retrieved from: