September heat wave set temperature records for Ottawa

By Patrick Barrios

Ottawa’s sweltering late-September heat wave smashed temperature records for the capital.

According to Environment Canada, Sept. 27 marked the conclusion of a six-day string of heat, which saw humidex values rising as high as 40 C. The 29.3 C temperature recorded on Sept. 23 was the hottest for that date since 1961, while the 33 C reached on Sept. 25 made it the hottest day in Ottawa for all of 2017.

For some, September’s sky-high temperatures were a welcome change following a summer that seemed to offer more rain than sunshine.

Nearly 176 mm of rain poured from the sky in May, making it the wettest May in Ottawa’s recorded history. The rainfall was more than double the average amount for the month, and caused flooding at many homes along riverbanks in Ottawa, Gatineau and throughout the Ottawa River watershed.

July was also stunningly wet, with its 249.8 mm the most rainfall in the region for that month since 1899. And not a single day what is normally Ottawa’s hottest month saw temperatures rise to 30 C.

However, September’s heat did have some consequences.

For students across Ottawa studying in classrooms without air conditioning, the heat was sometimes overwhelming and distracting. For farmers, it signaled further unpredictability in what had already been a difficult year for crops.

For some pet-owners who weren’t used to worrying about high temperatures once fall hits, the unexpected heat wave posed a dehydration danger and other risks for their pets.

“Usually, we’re putting on sweaters right now, not shorts, so it’s easy to see why keeping pets safe in the heat is not top of mind,” Bruce Honey, executive director the Ottawa Humane Society, said in statement during the heat wave. “Regardless, temperatures inside a car heat up really quickly, putting your dog at risk of heat stroke or worse. So keep your pet’s well-being in mind.”

Early October saw continued mildness but temperatures dropping closer to the normal range.