Purple Valley, ON F1 Tornado of June 2, 1999

Grey - Bruce

Touching down at 12:00 pm, the tornado demolished a pole barn, scattering debris for more than 1km, leaving some caught in fences and hanging from trees. In addition, timber poles were snapped in two and left impaled in the ground. Trees were snapped and uprooted, farm equipment and a tractor were thrown around, and a heavy combine was moved 15m.

The tornado travelled for 1km and had a path that was 100m wide. It was one of two tornadoes to touch down in Southern Ontario on June 2; the other was an F0 near Maple.

Figure 1 depicts the surface observations at 11:00 am, which depicts a strong low pressure system in northern Michigan with a stationary front extending into central Ontario and a cold front sweeping through the Great Lakes. Pre-frontal storms developed in southwestern Ontario, which ultimately led to this F1 tornado.

Figure 1. Surface analysis at 15Z on June 2, 1999 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 12:00 pm EDT near Purple Valley, ON. The tornado travelled for 1 km and had a maximum width of 50 metres. The tornado caused no fatalities or injuries, but caused $60 thousand dollars in property damage.


NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 15Z Wed Jun 2 1999. Retrieved from: https://www.wpc.ncep.noaa.gov/archives/web_pages/sfc/sfc_archive.php

Environment and Climate Change Canada Data. (2018). Canadian National Tornado Database: Verified Events (1980-2009) – Public. Retrieved from: http://donnees.ec.gc.ca/data/weather/products/canadian-national-tornado-database-verified-events-1980-2009-public/