Trader consensus on the Toronto high temperature market clusters around 17–18°C, reflecting the latest model guidance showing easterly to northeasterly flow advecting cooler maritime air and increasing cloud cover that limits insolation on September 19. Official Environment Canada forecasts project a 20°C high with afternoon clearing, while several private and global models (GFS, ECMWF) indicate values closer to 16–18°C under overcast conditions and dew points near 10°C. This spread creates genuine forecast uncertainty typical of transitional September patterns, where small shifts in cloud timing or wind direction can alter maximum temperatures by 1–2°C. Updated model runs and Environment Canada briefings over the next 24 hours will likely drive any market adjustments before 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 September 19?
Highest temperature in Toronto on September 19?
18°C 42%
17°C 34%
16°C 17%
19°C 9%
NEW
NEW
Sep 19, 2026
12°C or below
<1%
13°C
<1%
14°C
<1%
15°C
<1%
16°C
17%
17°C
34%
18°C
42%
19°C
9%
20°C
3%
21°C
1%
22°C or higher
<1%
18°C 42%
17°C 34%
16°C 17%
19°C 9%
NEW
NEW
Sep 19, 2026
12°C or below
$55 Vol.
<1%
13°C
$45 Vol.
<1%
14°C
$107 Vol.
<1%
15°C
$252 Vol.
<1%
16°C
$1,108 Vol.
17%
17°C
$658 Vol.
34%
18°C
$3,358 Vol.
42%
19°C
$345 Vol.
9%
20°C
$538 Vol.
3%
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.Trader consensus on the Toronto high temperature market clusters around 17–18°C, reflecting the latest model guidance showing easterly to northeasterly flow advecting cooler maritime air and increasing cloud cover that limits insolation on September 19. Official Environment Canada forecasts project a 20°C high with afternoon clearing, while several private and global models (GFS, ECMWF) indicate values closer to 16–18°C under overcast conditions and dew points near 10°C. This spread creates genuine forecast uncertainty typical of transitional September patterns, where small shifts in cloud timing or wind direction can alter maximum temperatures by 1–2°C. Updated model runs and Environment Canada briefings over the next 24 hours will likely drive any market adjustments before resolution.
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
$7,090End 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.Trader consensus on the Toronto high temperature market clusters around 17–18°C, reflecting the latest model guidance showing easterly to northeasterly flow advecting cooler maritime air and increasing cloud cover that limits insolation on September 19. Official Environment Canada forecasts project a 20°C high with afternoon clearing, while several private and global models (GFS, ECMWF) indicate values closer to 16–18°C under overcast conditions and dew points near 10°C. This spread creates genuine forecast uncertainty typical of transitional September patterns, where small shifts in cloud timing or wind direction can alter maximum temperatures by 1–2°C. Updated model runs and Environment Canada briefings over the next 24 hours will likely drive any market adjustments before resolution.
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
$7,090End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Trader consensus on the Toronto high temperature market clusters around 17–18°C, reflecting the latest model guidance showing easterly to northeasterly flow advecting cooler maritime air and increasing cloud cover that limits insolation on September 19. Official Environment Canada forecasts project a 20°C high with afternoon clearing, while several private and global models (GFS, ECMWF) indicate values closer to 16–18°C under overcast conditions and dew points near 10°C. This spread creates genuine forecast uncertainty typical of transitional September patterns, where small shifts in cloud timing or wind direction can alter maximum temperatures by 1–2°C. Updated model runs and Environment Canada briefings over the next 24 hours will likely drive any market adjustments before 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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