Official forecasts from Environment Canada and major models converge on a September 17 high of 22–24°C in Toronto under mostly cloudy skies with a 30–40% chance of light showers and northeast winds near 10 km/h. These conditions limit daytime heating by reducing solar radiation and promoting evaporative cooling, keeping the maximum temperature tightly clustered near the seasonal average of 21.7°C. Trader consensus reflected in the market probabilities favors 23–24°C because recent model runs show minimal spread and no strong warm-air advection. Resolution hinges on the official Environment Canada reading at Pearson Airport, with any late-afternoon clearing potentially pushing the peak slightly higher.
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 September 17?
Highest temperature in Toronto on September 17?
24°C 34%
23°C 31%
22°C 18%
25°C 17%
NEW
NEW
Sep 17, 2026
19°C or below
<1%
20°C
2%
21°C
3%
22°C
18%
23°C
31%
24°C
34%
25°C
17%
26°C
3%
27°C
2%
28°C
<1%
29°C or higher
<1%
24°C 34%
23°C 31%
22°C 18%
25°C 17%
NEW
NEW
Sep 17, 2026
19°C or below
$232 Vol.
<1%
20°C
$10 Vol.
2%
21°C
$409 Vol.
3%
22°C
$1,696 Vol.
18%
23°C
$827 Vol.
31%
24°C
$1,993 Vol.
34%
25°C
$966 Vol.
17%
26°C
$405 Vol.
3%
27°C
$219 Vol.
2%
28°C
$263 Vol.
<1%
29°C or higher
$158 Vol.
<1%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Official forecasts from Environment Canada and major models converge on a September 17 high of 22–24°C in Toronto under mostly cloudy skies with a 30–40% chance of light showers and northeast winds near 10 km/h. These conditions limit daytime heating by reducing solar radiation and promoting evaporative cooling, keeping the maximum temperature tightly clustered near the seasonal average of 21.7°C. Trader consensus reflected in the market probabilities favors 23–24°C because recent model runs show minimal spread and no strong warm-air advection. Resolution hinges on the official Environment Canada reading at Pearson Airport, with any late-afternoon clearing potentially pushing the peak slightly higher.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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 NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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: Sep 15, 2026, 8:56 AM ET
Volume
$7,179End Date
Sep 17, 2026Market Opened
Sep 15, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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.Official forecasts from Environment Canada and major models converge on a September 17 high of 22–24°C in Toronto under mostly cloudy skies with a 30–40% chance of light showers and northeast winds near 10 km/h. These conditions limit daytime heating by reducing solar radiation and promoting evaporative cooling, keeping the maximum temperature tightly clustered near the seasonal average of 21.7°C. Trader consensus reflected in the market probabilities favors 23–24°C because recent model runs show minimal spread and no strong warm-air advection. Resolution hinges on the official Environment Canada reading at Pearson Airport, with any late-afternoon clearing potentially pushing the peak slightly higher.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 17 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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 NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=cyyz
If NOAA data for the observation date is unavailable by 11:59 PM ET on the day following the observation date, the Weather Underground Daily Observations table will be used as the resolution source.
In the event that there is no data for the observation date by 11:59 PM ET on the day following the observation date, this market will resolve to the lowest bracket.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °C.
This market will resolve once the first data point for the following date has been published on the resolution source, or by 11:59 PM ET on the day following the observation date, whichever comes first.
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
$7,179End Date
Sep 17, 2026Market Opened
Sep 15, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Official forecasts from Environment Canada and major models converge on a September 17 high of 22–24°C in Toronto under mostly cloudy skies with a 30–40% chance of light showers and northeast winds near 10 km/h. These conditions limit daytime heating by reducing solar radiation and promoting evaporative cooling, keeping the maximum temperature tightly clustered near the seasonal average of 21.7°C. Trader consensus reflected in the market probabilities favors 23–24°C because recent model runs show minimal spread and no strong warm-air advection. Resolution hinges on the official Environment Canada reading at Pearson Airport, with any late-afternoon clearing potentially pushing the peak slightly higher.
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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