What's next? Is summer really over in Canada?

Wednesday, August 7, 2013, 11:29 AM -

This summer across Canada has been very different than last summer. When we compare seasons on a social level, we always remember the last few years. So just how has the summer been shaping up and what does the rest of August have in store?

Summer-So-Far in Review

Eastern Canada

When we speak about “summer” in meteorological terms, we’re referring to June, July and August. Taking a look back at June and July, we see a similar trend across many Eastern Canadian cities: normal temperatures and above average rainfall.

Montreal, Toronto, Fredericton and Halifax are a few of the cities whose June and July combined rainfall totals are above average. Montreal received roughly 240 mm of rain in June and July where 1981-2010 climate normals suggest roughly 180 mm to be the norm. Who in the Greater Toronto Area could forget the flooding in July? Over the first two summer months, Toronto has recorded about 280 mm of rain where normal rainfall amounts are roughly 150 mm.

(The Canadian Press)

The temperatures in Eastern Canada so far this summer have been a bit of a roller coaster. Much of June, the eastern half of the country was experiencing near normal or slightly below normal temperatures. That changed in July where most cities were at or above normal for the month. St. John’s, Newfoundland reached its second highest temperature on record climbing to 31.2°C on July 15. Towns across Ontario, Quebec and New Brunswick reached heat wave status mid-July with three consecutive days of 32°C or more (30°C in Quebec).

Let’s not forget about the severe weather across Eastern Canada? Five tornadoes were confirmed in Ontario in June and July, two in Quebec and even one EF-1 tornado near Grand Lake, New Brunswick that caused a great deal of damage. Tornadoes weren’t the only culprits: heavy, flooding rain wreaked havoc across the Greater Toronto Area at the beginning of July with Toronto’s Pearson International Airport receiving its greatest single day rainfall on record of 126 mm, beating out the previous record set by the remnants of Hurricane Hazel on October 15, 1954.

After the heat wave mid-July, the much needed relief for Eastern Canadians came with a bang: severe thunderstorms marched across Ontario and Quebec leaving swaths of damage in their paths. Large hail, localized flooding, houses damaged, trailers flipped, bands of trees flattened … Wind gusts as high as 120 km/h were reported in parts of southern Ontario.

Lightning strikes were common during the storm (Courtesy: Shahab Mirzaei)

Western Canada

The West was divided when it came to the weather so far this summer. British Columbia had a relatively normal June. Temperatures were normal, rainfall amounts were normal but things dried out in July. Little to no rainfall was being recorded across southern British Columbia. On average, Vancouver receives roughly 35 mm of rain in July. Not a single drop was recorded in all of July. Just after midnight, on the first day of August, Vancouver’s International Airport recorded a couple of millimeters of rain “breaking” the dry spell. July 2013 will now go down in the record books as Vancouver’s driest month on record.

Not only was July dry for British Columbians, it was sunny for many south coasters as well. Vancouver recorded its sunniest month on record with 411 hours of sunshine! Normal sunshine hours for Vancouver is 294.5 hours of sunshine in July. Victoria, the province’s capital, tied its previous sunshine record with 421.5 hours of sunshine in July.

The temperatures in the Prairies have been a ride this summer, so far. With warm spells and cold spells, it has been hard to keep up with the weather. July proved to be below normal for many major cities across the Prairies including Calgary, Regina and Saskatoon, Other places such as Edmonton and Winnipeg evened out to near normal for June and July. Rainfall amounts were fairly normal across the Prairies this summer with one very large exception: the devastating flooding that occurred in southern Alberta. A weather system was stuck over Alberta mid-June, dumping torrents of rain in the Foothills. About 190 mm fell in Bow Valley, Alberta. About 120 mm in Sundre and 90 mm in Banff. The heavy rain swamped rivers and towns downstream such as Calgary and High River were inundated were flood waters. The Weather Network has put together a special on the devastating Alberta flood, “Behind the Rising Water” which will be airing periodically this month. More details here.

Severe weather across the Prairies has also been the big story. As many as 20 tornadoes have been reported or confirmed in June and July across Alberta, Saskatchewan and Manitoba. Many summer days have been plagued with tornado warnings and sizable hail. On July 15, as many as seven tornadoes were reported across southern Saskatchewan. Two tornadoes struck the towns of Pipestone and Hartney, Manitoba leaving multiple homes damaged mid-July. A tornado was reported near the Okotoks airports in Alberta toward the end of July.

Tornado pic from SW MB Sunday #mbstorm RT @JanelleDawn19 Tornado! #weathernetwork #manitobastormwatch pic.twitter.com/oMprQoObgH

— Chris Scott (@ChrisScottWx) July 22, 2013

Physical scars from damaging storms can be seen from above via hot air balloon images and satellite images across parts of the Prairies.

July 6th hail swath from the vantage of a hot air balloon. Picture taken the day after the storm

Rest-of-Summer Preview

Most of Canada experienced an extended period of warmer than seasonal temperatures during early to mid-July. However, the end of July and the first week of August have brought an autumnal weather pattern to much of the country, especially to the Prairies, Ontario and Quebec. This has caused many to ask, “Is summer over?”

Overall, it looks like August will end up cooler than seasonal across southern Canada from southern Alberta to New Brunswick with the coolest temperatures relative to average found over the southern Prairies. However, summer is not over and we should still see some warm days during the month as it looks like the autumn-like weather pattern will relax for a while during the middle of the month.

Warmer than seasonal temperatures are expected over British Columbia, with near seasonal to above seasonal temperatures for the Nova Scotia, Prince Edward Island and Newfoundland.

August is part of the severe weather season across central and eastern Canada and August 2013 does have the potential to be rather active. Temperatures in the upper atmosphere will be colder than what we typically see during August and this will make the atmosphere more unstable.

August also takes us towards the peak of the hurricane season. An extensive area of dry air in the mid and upper levels of the atmosphere over the tropical Atlantic has limited tropical development thus far, but the tropics will become more active as we head into late August and September. Unfortunately, the weather pattern gives us a higher than typical threat for a couple of those systems to make landfall, but it is too early to determine whether that threat will primarily be over the United States or whether Atlantic Canada will be at risk as well. It is important for Atlantic Canadians to pay attention to tropical forecasts over the next couple of months as hurricane season continues.

Hurricane Sandy in 2012 was a cold-core extratropical cyclone, a storm type know to derive energy over land from the clashes between different air masses. (Courtesy: NASA's Earth Observatory)

August is normally quite an active month for forest fires in British Columbia. With record breaking dry weather in the province in July, this will be another area to keep an eye on as the month progresses. Fire danger ratings are High to Extreme for most of the province (except for southeastern portions).

Photo courtesy: White Lake Road wildfire, near Okanagan Falls, British Columbia, © Wildfire Management Branch of Ministry of Forests, Lands and Natural Resource Operations British Columbia