Recent model consensus from agencies like Environment Canada points to moderate high pressure and limited cloud cover over southern Ontario, supporting a Toronto high near the July climatological average of 26°C on July 21, which explains its leading 26% market-implied probability. Subtle variations in forecast guidance around lake-breeze effects from Lake Ontario, boundary-layer mixing, and any weak shortwave troughs create the tight clustering between 24–28°C outcomes, with traders weighting ensemble spreads that show only modest day-to-day warming potential. Urban heat-island amplification and dew-point trends add further uncertainty within this narrow range, while probabilities drop sharply above 29°C absent stronger subsidence or southerly flow. Updated model runs expected overnight will likely refine these distinctions ahead of resolution.
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 July 21?
Highest temperature in Toronto on July 21?
27°C 29%
26°C 26%
28°C 16%
25°C 16%
NEW
$14,328 Vol.
NEW
$14,328 Vol.
Jul 21, 2026
23°C or below
3%
24°C
9%
25°C
16%
26°C
26%
27°C
29%
28°C
16%
29°C
2%
30°C
1%
31°C
<1%
32°C
<1%
33°C or higher
<1%
27°C 29%
26°C 26%
28°C 16%
25°C 16%
NEW
$14,328 Vol.
NEW
$14,328 Vol.
Jul 21, 2026
23°C or below
$1,162 Vol.
3%
24°C
$1,694 Vol.
9%
25°C
$1,774 Vol.
16%
26°C
$1,320 Vol.
26%
27°C
$2,830 Vol.
29%
28°C
$2,493 Vol.
16%
29°C
$1,220 Vol.
2%
30°C
$222 Vol.
1%
31°C
$945 Vol.
<1%
32°C
$358 Vol.
<1%
33°C or higher
$310 Vol.
<1%
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 21 Jul '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Recent model consensus from agencies like Environment Canada points to moderate high pressure and limited cloud cover over southern Ontario, supporting a Toronto high near the July climatological average of 26°C on July 21, which explains its leading 26% market-implied probability. Subtle variations in forecast guidance around lake-breeze effects from Lake Ontario, boundary-layer mixing, and any weak shortwave troughs create the tight clustering between 24–28°C outcomes, with traders weighting ensemble spreads that show only modest day-to-day warming potential. Urban heat-island amplification and dew-point trends add further uncertainty within this narrow range, while probabilities drop sharply above 29°C absent stronger subsidence or southerly flow. Updated model runs expected overnight will likely refine these distinctions ahead of resolution.
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 21 Jul '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Market Opened: Jul 19, 2026, 9:06 PM ET
Volume
$14,328End Date
Jul 21, 2026Market Opened
Jul 19, 2026, 9:06 PM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZResolver
0x69c47De9D...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 21 Jul '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.Recent model consensus from agencies like Environment Canada points to moderate high pressure and limited cloud cover over southern Ontario, supporting a Toronto high near the July climatological average of 26°C on July 21, which explains its leading 26% market-implied probability. Subtle variations in forecast guidance around lake-breeze effects from Lake Ontario, boundary-layer mixing, and any weak shortwave troughs create the tight clustering between 24–28°C outcomes, with traders weighting ensemble spreads that show only modest day-to-day warming potential. Urban heat-island amplification and dew-point trends add further uncertainty within this narrow range, while probabilities drop sharply above 29°C absent stronger subsidence or southerly flow. Updated model runs expected overnight will likely refine these distinctions ahead of resolution.
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 21 Jul '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Toronto Pearson Intl Airport Station, 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 until the first data point for the following date has been published on the resolution source.
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.
Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Volume
$14,328End Date
Jul 21, 2026Market Opened
Jul 19, 2026, 9:06 PM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZResolver
0x69c47De9D...Recent model consensus from agencies like Environment Canada points to moderate high pressure and limited cloud cover over southern Ontario, supporting a Toronto high near the July climatological average of 26°C on July 21, which explains its leading 26% market-implied probability. Subtle variations in forecast guidance around lake-breeze effects from Lake Ontario, boundary-layer mixing, and any weak shortwave troughs create the tight clustering between 24–28°C outcomes, with traders weighting ensemble spreads that show only modest day-to-day warming potential. Urban heat-island amplification and dew-point trends add further uncertainty within this narrow range, while probabilities drop sharply above 29°C absent stronger subsidence or southerly flow. Updated model runs expected overnight will likely refine these distinctions ahead of resolution.
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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