The closely matched market odds around 12–13°C reflect uncertainty in the precise overnight minimum recorded at official Toronto stations on September 20, 2026, amid a cooler air mass and moderate northerly winds. Radiative cooling under partly cloudy skies, combined with dew point and humidity levels near 10–12°C, set the stage for a low near the 1991–2020 climatological average of 12.9°C. Light winds limited mixing while urban heat island effects and station siting differences introduced small observational variability. Forecasters from Environment Canada and model guidance converged on this range, with no extreme cold advection or clear-sky extremes to push values lower. Traders weighed these factors against historical September variability when assigning near-even probabilities to the top outcomes.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Toronto on September 20?
Lowest temperature in Toronto on September 20?
12°C 100%
11°C 90%
8°C or below 49%
10°C 20%
$179 Vol.
$179 Vol.
Sep 20, 2026
8°C or below
49%
9°C
12%
10°C
20%
11°C
90%
12°C
100%
13°C
51%
14°C
<1%
15°C
<1%
16°C
<1%
17°C
<1%
18°C or higher
<1%
12°C 100%
11°C 90%
8°C or below 49%
10°C 20%
$179 Vol.
$179 Vol.
Sep 20, 2026
8°C or below
$0 Vol.
49%
9°C
$15 Vol.
12%
10°C
$15 Vol.
20%
11°C
$15 Vol.
90%
12°C
$5 Vol.
100%
13°C
$9 Vol.
51%
14°C
$27 Vol.
<1%
15°C
$22 Vol.
<1%
16°C
$22 Vol.
<1%
17°C
$22 Vol.
<1%
18°C or higher
$27 Vol.
<1%
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 closely matched market odds around 12–13°C reflect uncertainty in the precise overnight minimum recorded at official Toronto stations on September 20, 2026, amid a cooler air mass and moderate northerly winds. Radiative cooling under partly cloudy skies, combined with dew point and humidity levels near 10–12°C, set the stage for a low near the 1991–2020 climatological average of 12.9°C. Light winds limited mixing while urban heat island effects and station siting differences introduced small observational variability. Forecasters from Environment Canada and model guidance converged on this range, with no extreme cold advection or clear-sky extremes to push values lower. Traders weighed these factors against historical September variability when assigning near-even probabilities to the top outcomes.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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 18, 2026, 8:29 AM ET
Volume
$179End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 closely matched market odds around 12–13°C reflect uncertainty in the precise overnight minimum recorded at official Toronto stations on September 20, 2026, amid a cooler air mass and moderate northerly winds. Radiative cooling under partly cloudy skies, combined with dew point and humidity levels near 10–12°C, set the stage for a low near the 1991–2020 climatological average of 12.9°C. Light winds limited mixing while urban heat island effects and station siting differences introduced small observational variability. Forecasters from Environment Canada and model guidance converged on this range, with no extreme cold advection or clear-sky extremes to push values lower. Traders weighed these factors against historical September variability when assigning near-even probabilities to the top outcomes.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Toronto Pearson Intl Airport Station in degrees Celsius on 20 Sep '26.
The resolution source for this market will be information from NOAA, specifically the lowest 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 lowest 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
$179End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...The closely matched market odds around 12–13°C reflect uncertainty in the precise overnight minimum recorded at official Toronto stations on September 20, 2026, amid a cooler air mass and moderate northerly winds. Radiative cooling under partly cloudy skies, combined with dew point and humidity levels near 10–12°C, set the stage for a low near the 1991–2020 climatological average of 12.9°C. Light winds limited mixing while urban heat island effects and station siting differences introduced small observational variability. Forecasters from Environment Canada and model guidance converged on this range, with no extreme cold advection or clear-sky extremes to push values lower. Traders weighed these factors against historical September variability when assigning near-even probabilities to the top outcomes.
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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