After a fairly comfortable start to the week, southern Ontario is getting a late-season reminder that it's still summer out there, as the mercury is expected to skyrocket today and tomorrow, and it will be pushing the humidex up along with it, to as high as 45 in some areas.
Temperatures across southern Ontario will be climbing into the 30s today, with southwestern Ontario expected to see the worst of it. The hottest forecast is 35°C, for Windsor, but the rest of the southwest won't be too far behind. Toronto will likely reach 34°C this afternoon, and the rest of the southwest will likely see temperatures just shy of what residents of the GTA and Windsor will be enduring. Further east, the heat tapers off, with Ottawa and Kingston only expected to get up into the high 20s.
With the normal temperatures for this time of year typically in the low 20s, today's mercury readings are poised to break records. 34°C in Toronto may be the highest temperature the city has seen so far this year. While that isn't a record in of itself, it's just shy of breaking an 11 year old record for the day (34.8°C from 2002), so we'll have to see just how hot it gets. Windsor's forecast of 35°C is one degree higher than the current September 10th record, set 30 years ago, in 1983. Hamilton's forecast comes close to their record of 32.7°C from the same year.
[ Related: Get the latest forecast at Yahoo Weather ]
It could be an interesting day for weather records, but as always, it won't so much be the heat as the humidity, as the warm southwesterly winds are also bringing in a flow of humid air all the way from the Gulf of Mexico. This is guaranteeing a sticky, uncomfortable couple of days for southern Ontario, with humidex values pushing up into the 40s. This has prompted Environment Canada to issue a Humidex Advisory for all of southwestern and central Ontario, and east as far as Smiths Falls and Sharbot Lake.
The City of Toronto has issued a Heat Alert for today, opening up numerous cooling stations around the city to help residents beat the heat. The City of London has declared a Heat Alert as well, and the City of Hamilton has called a Heat Advisory for today. Other cities throughout southern Ontario don't necessarily issue their own alerts and advisories in these situations, but they do step up when Environment Canada issues a humidex advisory. Kitchener is an excellent example, as they open up cooling centres and keep splash parks, outdoor and indoor pools open for extended hours.
Recommendations for this kind of weather are to stay out of the heat as much as you can, and if you do need to be outside for any length of time, make sure you stay hydrated and take frequent breaks from the heat.
[ More Geekquinox: Risk of record heat now four times what it was in pre-industrial times ]
The heat and humidity are expected to be a little less unbearable for Wednesday, but it won't completely let up until later on Wednesday afternoon or early evening, when a cold front is expected to sweep through. This is expected to return us to more seasonal weather for the rest of the week.
(Photo courtesy: The Canadian Press)
Geek out with the latest in science and weather.
Follow @ygeekquinox on Twitter!