Top ten weather stories for 2011: story seven

On the first day of astronomical summer, June 21, temperatures were on the rise from Saskatchewan to Quebec, blanketing millions of Canadians in warmth and sunshine. In the midst of summer’s dog days, the mercury often bubbled into the 30s, with the humidity making it feel like the 40s. Extreme as it was, many Canadians seemed to enjoy the sun and the sweat, possibly because of a winter that had been long and tough at times and a cool, wet spring.

July was especially hot from Brandon to Beaconsville and from Windsor to Wabush. The heat was unrelenting under a continental-sized dome of high pressure that covered 40 states and four provinces.  Dozens of sites broke temperature records for both night and day. Windsor, arguably Canada’s hottest city, recorded its warmest July ever. The mean daily temperature was three degrees above normal at 25.9°C. No major city in Canada has ever recorded a higher mean temperature. Windsor also reached another weather milestone with its hottest day ever. On July 21, the average daily temperature in Windsor was 32.1°C. Amidst the heat and humidity was some welcome relief – little smog or haze to be found. Additionally, humidex values peaked in the upper 40s across Ontario and Quebec, with one observing site in Toronto recording a humidex of nearly 51. In Quebec, new sweltering temperature records were set in Montreal, Sherbrooke and l’Assomption. The hottest temperature occurred at St-Hubert at 36.0ºC. Farther west, Winnipeg’s seemingly endless summer registered 24 days when the daytime high rose above 30°C, exceeding the total for the past three years combined. Its hottest day was the warmest in 16 years: 37.2°C on August 23. To the delight of residents, it rained only four Saturdays and Sundays out of 27, resulting in perfect weekend weather for almost the entire summer.

Across central Canada, health officials issued dozens of heat alerts. For one hour on July 21, electricity demand in Ontario skyrocketed to about 25,300 megawatts – the highest it had been in four years. In Toronto, worry about the health and safety of sports fans and players resulted in the Blue Jays ball club keeping the retractable roof at Rogers Centre closed for a matinee game. In Montreal, health experts attributed the death of 10 people to the prolonged extreme heat. Hospital admissions in the city spiked during the heat wave, and police officers and firefighters went door-to-door to check on residents.

For those on the west and east coasts, it was a different story altogether as they endured cool temperatures, endless rain and overcast or foggy skies. In Atlantic Canada, summer temperatures were near normal, but there was no denying how wet it was – some 20 per cent wetter than normal. Fredericton had its wettest July and August ever. In Moncton, May, June, July and August were the rainiest on record. The monotony of the damp weather made it even more unbearable. The longest stretch of rain-free days in May and June was just two days; in July it was three days. During one foul spell, Halifax featured a string of 35 wet days out of 40. In venerably wet St. John’s, residents cursed the relentless rains. During one miserable stretch of weather between July 12 and August 14, it rained on 32 of 33 days. On the flip side, Atlantic Canada did get some great summer weather – it just didn’t show up until September when people had returned to school and/or work. And as is often the case on the East Coast, the fall was spectacular; this year even more so with record warm temperatures.

In the West, residents of coastal British Columbia often have to endure a couple of weeks of cool, cloudy and wet weather (called the June gloom or Junuary) before summer inevitably takes hold. Sometimes it occurs earlier, sometimes later, but rarely does it persist from April to July as it did in 2011. Meteorologists blamed the inclement weather on the hangover effects of La Niña and cooler sea surface temperatures. Unfortunately for residents and visitors in the B.C. Interior and Alberta, the cool, cloudy, coastal weather extended farther east than normal and persisted through June and July. Edmonton recorded 280 mm of rain during those two months, making it the wettest beginning to summer on record. The long spate of dark, damp and dank weather was tough on everyone – especially gardeners, farmers and vintners. The lack of sunshine slowed the ripening process and meant fruit was less sweet. August finally brought long-awaited summer heat and sunny skies to southern B.C. Vancouver had just one day of rain in August, well below the monthly average of seven, and featured 53 more hours of sunshine than normal for the month. Fortunately for all, the warmth and sunshine continued into early September.