Potential for Ontario's warmest start to October in 100 years

Potential for Ontario's warmest start to October in 100 years
Potential for Ontario's warmest start to October in 100 years

The start of October will be warmer than the start of August.

There, now I’ve got your attention.

You’re all too familiar with the current pattern across Ontario, but a buzz is building on social media after computer models spit out egregiously high temperatures next week.

RELATED: Why storms will bypass Toronto and surrounding cities for at least another week

A persistent high-pressure ridge has enveloped Ontario for two weeks. The hottest stretch of weather will flare up as soon as we flip the calendar into October.

First, we can look at the first seven days of October for some locations across Ontario -- to gauge the warmest years on record.


1900, 1962, and 2005 all have some of the warmest, average highs during the first week of October. The extent of the heat will be sprawling, even pushing towards Timmins, Ont., which has never averaged over 20°C for daytime highs during this period.

Farther south, the Greater Toronto Area (GTA) is on the cusp of documenting the warmest start to October in recorded history. That will be the case if Toronto averages 25°C or warmer to start the month. Even if it falls short, an average high temperature above 24.3°C will mean it’s the hottest start to October since 1922.

October of 1900 was even warmer, averaging 24.9°C when the city had a population of just 200,000. Compare that to the chilliest start to October in recent memory, where 1999 featured an average high under 12°C!

There are a couple of factors driving the warmth we're experiencing, including a stubborn, high-pressure system across the U.S. that's sandwiched between two cut-off upper lows. This pattern is called an "omega block," which causes a blockage in the atmosphere. Essentially, what we're seeing is what we're getting.


The region is being dragged through a drawn-out dry spell, turning lawns brown and stressing the natural flora. We have high confidence the next seven days will remain dry across the GTA and eastern Ontario, extending the days without rainfall to more than 20. The summer was exceedingly wet across southern Ontario; consequently, that’s provided a buffer to spiralling into drought conditions, but there’s little doubt it’s now abnormally dry.

With the potential for the warmest start to October on record, it fits into the global climate context. August was the warmest on record across North America, including the Arctic. Current wildfires burning across the country are a testament to this, as smoke swirls around the globe.

What’s next? As Ontario looks to endure one of the warmest starts to October on record, be on the lookout for our monthly outlook this Sunday, highlighting when we will expect a pattern change to develop.

WATCH: Greenland is billowing in smoke from Canadian wildfires

Click here to view the video

Thumbnail courtesy of Getty Images-611335120.