Recent forecasts from Environment Canada, GFS ensembles, and other models indicate a high near 17–18 °C for Toronto on September 19, driven by increasing easterly flow and persistent cloud cover that limits daytime heating. This positions the market’s heaviest trading on 18 °C (48.5 %) and 17 °C (34.5 %), well below the late-September climatological average of roughly 21 °C. Minor model spread keeps 16 °C and 19 °C viable but lower-probability outcomes, while extremes remain negligible given the stable synoptic pattern and absence of strong warm or cold advection. Updated model runs and official briefings tomorrow morning will provide the final observational constraints before the daily maximum is recorded.
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 19?
Highest temperature in Toronto on September 19?
18°C 48%
17°C 35%
16°C 13%
19°C 8%
NEW
NEW
Sep 19, 2026
12°C or below
<1%
13°C
<1%
14°C
<1%
15°C
<1%
16°C
13%
17°C
35%
18°C
48%
19°C
8%
20°C
2%
21°C
1%
22°C or higher
<1%
18°C 48%
17°C 35%
16°C 13%
19°C 8%
NEW
NEW
Sep 19, 2026
12°C or below
$55 Vol.
<1%
13°C
$45 Vol.
<1%
14°C
$107 Vol.
<1%
15°C
$144 Vol.
<1%
16°C
$870 Vol.
13%
17°C
$624 Vol.
35%
18°C
$2,507 Vol.
48%
19°C
$345 Vol.
8%
20°C
$533 Vol.
2%
21°C
$400 Vol.
1%
22°C or higher
$225 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 19 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.Recent forecasts from Environment Canada, GFS ensembles, and other models indicate a high near 17–18 °C for Toronto on September 19, driven by increasing easterly flow and persistent cloud cover that limits daytime heating. This positions the market’s heaviest trading on 18 °C (48.5 %) and 17 °C (34.5 %), well below the late-September climatological average of roughly 21 °C. Minor model spread keeps 16 °C and 19 °C viable but lower-probability outcomes, while extremes remain negligible given the stable synoptic pattern and absence of strong warm or cold advection. Updated model runs and official briefings tomorrow morning will provide the final observational constraints before the daily maximum is recorded.
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 19 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 17, 2026, 8:56 AM ET
Volume
$5,855End Date
Sep 19, 2026Market Opened
Sep 17, 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 19 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.Recent forecasts from Environment Canada, GFS ensembles, and other models indicate a high near 17–18 °C for Toronto on September 19, driven by increasing easterly flow and persistent cloud cover that limits daytime heating. This positions the market’s heaviest trading on 18 °C (48.5 %) and 17 °C (34.5 %), well below the late-September climatological average of roughly 21 °C. Minor model spread keeps 16 °C and 19 °C viable but lower-probability outcomes, while extremes remain negligible given the stable synoptic pattern and absence of strong warm or cold advection. Updated model runs and official briefings tomorrow morning will provide the final observational constraints before the daily maximum is recorded.
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 19 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
$5,855End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Recent forecasts from Environment Canada, GFS ensembles, and other models indicate a high near 17–18 °C for Toronto on September 19, driven by increasing easterly flow and persistent cloud cover that limits daytime heating. This positions the market’s heaviest trading on 18 °C (48.5 %) and 17 °C (34.5 %), well below the late-September climatological average of roughly 21 °C. Minor model spread keeps 16 °C and 19 °C viable but lower-probability outcomes, while extremes remain negligible given the stable synoptic pattern and absence of strong warm or cold advection. Updated model runs and official briefings tomorrow morning will provide the final observational constraints before the daily maximum is recorded.
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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