Goose Lake, ON F1 Tornado of July 4, 2003

Sandy Lake - Pikangikum

Figure 1 depicts the surface observations at 1:00 pm CDT, which shows a low pressure system on the Manitoba/Ontario border with a trough extending into northwestern Ontario. This trough became the focus for thunderstorm development in the early afternoon of July 4th, which ultimately led to this F1 tornado.

Figure 1. Surface analysis at 18Z on July 4, 2003 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 at 2:15 pm CDT near Goose Lake, ON. The tornado travelled for 16.2 km with a maximum width of 490 metres. The tornado caused no fatalities, injuries or property damage.


NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 18Z Fri Jul 4 2003. Retrieved from:

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