Latest numerical weather prediction runs from Environment Canada and global models show high uncertainty for Toronto's August 31 maximum, with ensemble guidance clustering between 22–24 °C due to a weak surface high, modest warm-air advection, and variable cloud cover. Lake Ontario's moderating influence and potential lake-breeze timing create key spread in afternoon peaks, while urban heat-island effects and boundary-layer moisture add local variability. Historical late-August climatology places the 30-year average near 23 °C, aligning with the tight market-implied odds between the top three outcomes. Traders are weighting the most recent 00Z and 12Z model cycles heavily, with resolution hinging on official hourly observations 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 August 31?
Highest temperature in Toronto on August 31?
23°C 33%
24°C 30%
22°C 22%
21°C 8%
NEW
NEW
Aug 31, 2026
17°C or below
<1%
18°C
<1%
19°C
1%
20°C
2%
21°C
8%
22°C
22%
23°C
33%
24°C
30%
25°C
5%
26°C
1%
27°C or higher
<1%
23°C 33%
24°C 30%
22°C 22%
21°C 8%
NEW
NEW
Aug 31, 2026
17°C or below
$278 Vol.
<1%
18°C
$228 Vol.
<1%
19°C
$148 Vol.
1%
20°C
$59 Vol.
2%
21°C
$722 Vol.
8%
22°C
$646 Vol.
22%
23°C
$887 Vol.
33%
24°C
$1,504 Vol.
30%
25°C
$336 Vol.
5%
26°C
$188 Vol.
1%
27°C or higher
$333 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 31 Aug '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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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.Latest numerical weather prediction runs from Environment Canada and global models show high uncertainty for Toronto's August 31 maximum, with ensemble guidance clustering between 22–24 °C due to a weak surface high, modest warm-air advection, and variable cloud cover. Lake Ontario's moderating influence and potential lake-breeze timing create key spread in afternoon peaks, while urban heat-island effects and boundary-layer moisture add local variability. Historical late-August climatology places the 30-year average near 23 °C, aligning with the tight market-implied odds between the top three outcomes. Traders are weighting the most recent 00Z and 12Z model cycles heavily, with resolution hinging on official hourly observations at Pearson Airport.
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 31 Aug '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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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 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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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: Aug 29, 2026, 8:55 AM ET
Volume
$5,329End Date
Aug 31, 2026Market Opened
Aug 29, 2026, 8:55 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 31 Aug '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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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.Latest numerical weather prediction runs from Environment Canada and global models show high uncertainty for Toronto's August 31 maximum, with ensemble guidance clustering between 22–24 °C due to a weak surface high, modest warm-air advection, and variable cloud cover. Lake Ontario's moderating influence and potential lake-breeze timing create key spread in afternoon peaks, while urban heat-island effects and boundary-layer moisture add local variability. Historical late-August climatology places the 30-year average near 23 °C, aligning with the tight market-implied odds between the top three outcomes. Traders are weighting the most recent 00Z and 12Z model cycles heavily, with resolution hinging on official hourly observations at Pearson Airport.
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 31 Aug '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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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 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.
To toggle between Fahrenheit and Celsius, click the "Switch to Metric Units" button until the relevant table displays °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
$5,329End Date
Aug 31, 2026Market Opened
Aug 29, 2026, 8:55 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Latest numerical weather prediction runs from Environment Canada and global models show high uncertainty for Toronto's August 31 maximum, with ensemble guidance clustering between 22–24 °C due to a weak surface high, modest warm-air advection, and variable cloud cover. Lake Ontario's moderating influence and potential lake-breeze timing create key spread in afternoon peaks, while urban heat-island effects and boundary-layer moisture add local variability. Historical late-August climatology places the 30-year average near 23 °C, aligning with the tight market-implied odds between the top three outcomes. Traders are weighting the most recent 00Z and 12Z model cycles heavily, with resolution hinging on official hourly observations 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
Beware of external links.
Beware of external links.
Frequently Asked Questions