Summerstown, ON F0 Tornado of July 17, 2012

Cornwall - Morrisburg

F0 damage occurred at farms as this tornado touched down in the Summerstown area. Along a path that was 2 km long and 30 metres wide, the tornado cause sporadic tree and crop damage. It touched down at around 1:45 pm near the town about 15 km to the east of Cornwall. This was one of two tornadoes to touch down on July 17, 2012. The other occurred at Athens (F1).

Figure 1. Surface analysis at 21Z on July 17, 2012 showing mean sea-level pressure (MSLP) contours, surface observations, fronts and pressure centres (WPC, 2017)

Figure 1 depicts the surface observations at 5:00 pm EDT, which shows a cold front moving from northern Ontario through southern Ontario. This front became the primary mechanism for initiating severe thunderstorms throughout the afternoon hours of July 17th, which ultimately led to two tornadoes across southern Ontario.


NWS Weather Prediction Center Surface Analysis Archive. (2017). Surface analysis 21Z Tue Jul 17 2012. Retrieved from: