Recent official forecasts from Environment Canada project a sunny high near 31°C for Toronto on May 18, driven by a strong southerly flow advecting warm air masses under building high pressure. This setup favors rapid daytime heating with minimal cloud cover, though subtle differences in model guidance on afternoon boundary-layer mixing and any late-day convective development create uncertainty between 29°C and 32°C peaks. Such temperatures would exceed the May climatological average of roughly 20°C by a wide margin, with the market’s tight clustering around these outcomes reflecting trader assessment of ensemble spread and the narrow window for resolution at Pearson Airport.
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 18?
Highest temperature in Toronto on May 18?
29°C 28%
30°C 25%
31°C 23%
32°C or higher 20%
NEW
$11,836 Vol.
NEW
$11,836 Vol.
May 18, 2026
22°C or below
<1%
23°C
<1%
24°C
<1%
25°C
1%
26°C
2%
27°C
5%
28°C
9%
29°C
28%
30°C
25%
31°C
23%
32°C or higher
20%
29°C 28%
30°C 25%
31°C 23%
32°C or higher 20%
NEW
$11,836 Vol.
NEW
$11,836 Vol.
May 18, 2026
22°C or below
$3,682 Vol.
<1%
23°C
$1,023 Vol.
<1%
24°C
$1,534 Vol.
<1%
25°C
$500 Vol.
1%
26°C
$1,201 Vol.
2%
27°C
$487 Vol.
5%
28°C
$1,002 Vol.
9%
29°C
$896 Vol.
28%
30°C
$356 Vol.
25%
31°C
$525 Vol.
23%
32°C or higher
$1,028 Vol.
20%
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 18 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.Recent official forecasts from Environment Canada project a sunny high near 31°C for Toronto on May 18, driven by a strong southerly flow advecting warm air masses under building high pressure. This setup favors rapid daytime heating with minimal cloud cover, though subtle differences in model guidance on afternoon boundary-layer mixing and any late-day convective development create uncertainty between 29°C and 32°C peaks. Such temperatures would exceed the May climatological average of roughly 20°C by a wide margin, with the market’s tight clustering around these outcomes reflecting trader assessment of ensemble spread and the narrow window for resolution at Pearson Airport.
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 18 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 16, 2026, 12:03 AM ET
Volume
$11,836End Date
May 18, 2026Market Opened
May 16, 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 18 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.Recent official forecasts from Environment Canada project a sunny high near 31°C for Toronto on May 18, driven by a strong southerly flow advecting warm air masses under building high pressure. This setup favors rapid daytime heating with minimal cloud cover, though subtle differences in model guidance on afternoon boundary-layer mixing and any late-day convective development create uncertainty between 29°C and 32°C peaks. Such temperatures would exceed the May climatological average of roughly 20°C by a wide margin, with the market’s tight clustering around these outcomes reflecting trader assessment of ensemble spread and the narrow window for resolution at Pearson Airport.
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 18 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
$11,836End Date
May 18, 2026Market Opened
May 16, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZRecent official forecasts from Environment Canada project a sunny high near 31°C for Toronto on May 18, driven by a strong southerly flow advecting warm air masses under building high pressure. This setup favors rapid daytime heating with minimal cloud cover, though subtle differences in model guidance on afternoon boundary-layer mixing and any late-day convective development create uncertainty between 29°C and 32°C peaks. Such temperatures would exceed the May climatological average of roughly 20°C by a wide margin, with the market’s tight clustering around these outcomes reflecting trader assessment of ensemble spread and the narrow window for resolution at Pearson Airport.
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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