Hot humid summery day for Montreal - powerful Iowa tornado

Strong thunderstorms across eastern Ontario began to weaken before reaching Ile Perrot and Montreal. They still managed to produce this spectacular gust front around 7pm, along with winds over 70km/h and 10mm of rain in just a few minutes (ValleyWeather Photo).

Summer weather has streamed into southern Quebec and eastern Ontario over the last 36 hours, along with elevated heat and humidity and scattered strong thunderstorms. The temperature on Tuesday climbed into the high 20s close to 30C for many parts of the region. This was followed by a strong cluster of thunderstorms that pushed across eastern Ontario. 

The storms produced a spectacular shelf cloud along the leading edge as it moved across Montreal during the supper hour, as well as a wind gusts over 70km/h at Trudeau Airport and around 10mm of rain on Ile Perrot. As the storms moved southeast of Montreal around 7pm, a rainbow appeared across the eastern sky, the calm after the storm.

We can expect similar weather on Wednesday, as partial sunshine will push high temperatures close to 30C (86F) in Montreal. Along with the humidity, temperatures will feel close to 37C. More thunderstorms are expected to develop this evening until around midnight. Some may be on the strong side once again.

Cooler, drier air will return on Thursday, with temperatures and humidity levels lowering. There will be a risk of some early morning showers in the Montreal region.

Heartbreaking damage from the small town of Greenfield, Iowa, which was nearly wiped off the map late Tuesday afternoon after a powerful tornado hit. It was one of nearly 815 tornadoes that have been reported already in 2024. (Photo: Chris Juhn via Fox Weather)

IOWA TORNADO

This has been a devastating tornado season stateside, with several long-lasting, wide and powerful tornadoes occurring already. Tuesday was no different, as the target this time was the central plains into the midwest. A strong tondo tore through the small community of Greenfield, Iowa, destroying the town, leveling homes to their foundations, tossing cars around, injuring and killing several residents. 

The storm has yet to be rated by the National Weather Service, but the damage looks eerily like that associated with an EF-5 storm. The Enhance Fujita Scale (EF) ranges from EF-0 to EF-5. An EF-5 tornado is capable of winds in excess of 200 mph (323 km/h). While there have been many storms that have come close to that rating over the last 10 years, there has not been an EF-5 tornado since the Moore, Oklahoma storm on May 20, 2013.

There has officially been only one EF-5 tornado observed in Canada, at Elie, Manitoba on June 22, 2007.