Ottawa's rainy summer may lead to extra vibrant fall colours, botanist predicts

While record-setting rainfall dampened summertime fun for many Ottawa residents, the wet weather could help fall foliage develop an extra vibrant burst of colour this year.

Paul Sokoloff, who is a botanist with the Canadian Museum of Nature, anticipates that the rainy summer could delay extraordinary shades of red, green and yellow on leaves, but predicts it'll be worth the wait.

"In order for the leaves to change colour and get those really vibrant hues, we need a combination of sunny days and cold nights,” Sokoloff said.

He expects trees won’t be blazing with colour until more crisp fall weather arrives later in October.

‘A very wet Ottawa summer’

July was the rainiest month in Ottawa since the city first started collecting weather data more than 150 years ago.

With a record 281.8 millimetres of rain recorded at the Ottawa International Airport, it broke the city’s previous monthly record of 250.2 millimetres from 1899, due to the July 1 storm and flash floods.

According to Sokoloff, a lack of moisture contributes to leaves immediately turning brown and slipping from trees, but the excess rainfall over the summer could have the opposite effect.

“Because it has been a very wet Ottawa summer, what we're probably going to have is a lot of photosynthesis continuing in the leaves,” he said.

As a result, trees will have enough moisture to continue converting sunlight into energy and keep their leaves longer.

The best spots for fall colours

Sokoloff says vast areas like Gatineau Park often get the first taste of fall scenery because the park experiences brisk, autumnal weather earlier, while Ottawa and Gatineau’s urban core stays warm longer because of its concrete infrastructure retaining heat.

“Head into your local wild area,” he said. “You're probably going to see the fall colours there a little bit earlier.”

Thumbnail courtesy of Janet Stephens (file photo, not current scenery), taken in Ottawa, Ont.

The story was originally written by and published for CBC News.