Current weather model consensus from the Global Forecast System and Canadian GEM ensembles points to a high near 23–25°C for Toronto on May 17, with the tight spread among leading outcomes reflecting modest uncertainty in afternoon boundary-layer heating. A strengthening southwesterly flow ahead of an approaching trough will enhance warm-air advection while light to moderate cloud cover limits peak solar insolation. Variable lake-breeze effects from Lake Ontario could cap temperatures if winds shift onshore, whereas delayed mixing or clearer breaks would favor the upper end of the range. Mid-May climatology shows typical highs near 19–21°C, so recent model runs trending 2–4°C warmer explain the current market clustering around 24°C. Hourly observations from Toronto Pearson will resolve the outcome by early evening.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Toronto on May 17?
Highest temperature in Toronto on May 17?
24°C 31%
23°C 26%
25°C 22%
22°C 9%
NEW
$12,429 Vol.
NEW
$12,429 Vol.
May 17, 2026
17°C or below
<1%
18°C
<1%
19°C
1%
20°C
2%
21°C
4%
22°C
9%
23°C
26%
24°C
31%
25°C
22%
26°C
7%
27°C or higher
2%
24°C 31%
23°C 26%
25°C 22%
22°C 9%
NEW
$12,429 Vol.
NEW
$12,429 Vol.
May 17, 2026
17°C or below
$3,245 Vol.
<1%
18°C
$1,476 Vol.
<1%
19°C
$1,309 Vol.
1%
20°C
$893 Vol.
2%
21°C
$653 Vol.
4%
22°C
$748 Vol.
9%
23°C
$810 Vol.
26%
24°C
$635 Vol.
31%
25°C
$541 Vol.
22%
26°C
$716 Vol.
7%
27°C or higher
$1,405 Vol.
2%
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Current weather model consensus from the Global Forecast System and Canadian GEM ensembles points to a high near 23–25°C for Toronto on May 17, with the tight spread among leading outcomes reflecting modest uncertainty in afternoon boundary-layer heating. A strengthening southwesterly flow ahead of an approaching trough will enhance warm-air advection while light to moderate cloud cover limits peak solar insolation. Variable lake-breeze effects from Lake Ontario could cap temperatures if winds shift onshore, whereas delayed mixing or clearer breaks would favor the upper end of the range. Mid-May climatology shows typical highs near 19–21°C, so recent model runs trending 2–4°C warmer explain the current market clustering around 24°C. Hourly observations from Toronto Pearson will resolve the outcome by early evening.
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: May 15, 2026, 12:03 AM ET
Volume
$12,429End Date
May 17, 2026Market Opened
May 15, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZThis market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Current weather model consensus from the Global Forecast System and Canadian GEM ensembles points to a high near 23–25°C for Toronto on May 17, with the tight spread among leading outcomes reflecting modest uncertainty in afternoon boundary-layer heating. A strengthening southwesterly flow ahead of an approaching trough will enhance warm-air advection while light to moderate cloud cover limits peak solar insolation. Variable lake-breeze effects from Lake Ontario could cap temperatures if winds shift onshore, whereas delayed mixing or clearer breaks would favor the upper end of the range. Mid-May climatology shows typical highs near 19–21°C, so recent model runs trending 2–4°C warmer explain the current market clustering around 24°C. Hourly observations from Toronto Pearson will resolve the outcome by early evening.
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$12,429End Date
May 17, 2026Market Opened
May 15, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZCurrent weather model consensus from the Global Forecast System and Canadian GEM ensembles points to a high near 23–25°C for Toronto on May 17, with the tight spread among leading outcomes reflecting modest uncertainty in afternoon boundary-layer heating. A strengthening southwesterly flow ahead of an approaching trough will enhance warm-air advection while light to moderate cloud cover limits peak solar insolation. Variable lake-breeze effects from Lake Ontario could cap temperatures if winds shift onshore, whereas delayed mixing or clearer breaks would favor the upper end of the range. Mid-May climatology shows typical highs near 19–21°C, so recent model runs trending 2–4°C warmer explain the current market clustering around 24°C. Hourly observations from Toronto Pearson will resolve the outcome by early evening.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
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