Current forecast models, including GFS runs and outputs from agencies like Environment Canada and the Met Office, point to overnight lows near 13–15°C for Toronto on September 20, driven by persistent cloud cover, light showers, and northeast winds that limit radiative cooling. These conditions align with historical September averages around 13°C while reducing the chance of sharp drops below 10°C. Market-implied odds favoring 18°C or higher at 49% appear anchored in model consensus on mild advection and uncertainty in exact timing of any clearing, though probabilities clustered around 11–14°C (19–24%) reflect the baseline expectation of moderate cooling. Updated model runs and official observations in the final hours before resolution remain the key variables for traders.
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?
18°C or higher 98%
8°C or below 50%
11°C 40%
13°C 40%
NEW
NEW
Sep 20, 2026
8°C or below
50%
9°C
17%
10°C
17%
11°C
40%
12°C
39%
13°C
24%
14°C
40%
15°C
39%
16°C
39%
17°C
17%
18°C or higher
98%
18°C or higher 98%
8°C or below 50%
11°C 40%
13°C 40%
NEW
NEW
Sep 20, 2026
8°C or below
$0 Vol.
50%
9°C
$0 Vol.
17%
10°C
$0 Vol.
17%
11°C
$0 Vol.
40%
12°C
$0 Vol.
39%
13°C
$5 Vol.
24%
14°C
$0 Vol.
40%
15°C
$0 Vol.
39%
16°C
$0 Vol.
39%
17°C
$0 Vol.
17%
18°C or higher
$0 Vol.
98%
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.Current forecast models, including GFS runs and outputs from agencies like Environment Canada and the Met Office, point to overnight lows near 13–15°C for Toronto on September 20, driven by persistent cloud cover, light showers, and northeast winds that limit radiative cooling. These conditions align with historical September averages around 13°C while reducing the chance of sharp drops below 10°C. Market-implied odds favoring 18°C or higher at 49% appear anchored in model consensus on mild advection and uncertainty in exact timing of any clearing, though probabilities clustered around 11–14°C (19–24%) reflect the baseline expectation of moderate cooling. Updated model runs and official observations in the final hours before resolution remain the key variables for traders.
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
$5End 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.Current forecast models, including GFS runs and outputs from agencies like Environment Canada and the Met Office, point to overnight lows near 13–15°C for Toronto on September 20, driven by persistent cloud cover, light showers, and northeast winds that limit radiative cooling. These conditions align with historical September averages around 13°C while reducing the chance of sharp drops below 10°C. Market-implied odds favoring 18°C or higher at 49% appear anchored in model consensus on mild advection and uncertainty in exact timing of any clearing, though probabilities clustered around 11–14°C (19–24%) reflect the baseline expectation of moderate cooling. Updated model runs and official observations in the final hours before resolution remain the key variables for traders.
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
$5End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Current forecast models, including GFS runs and outputs from agencies like Environment Canada and the Met Office, point to overnight lows near 13–15°C for Toronto on September 20, driven by persistent cloud cover, light showers, and northeast winds that limit radiative cooling. These conditions align with historical September averages around 13°C while reducing the chance of sharp drops below 10°C. Market-implied odds favoring 18°C or higher at 49% appear anchored in model consensus on mild advection and uncertainty in exact timing of any clearing, though probabilities clustered around 11–14°C (19–24%) reflect the baseline expectation of moderate cooling. Updated model runs and official observations in the final hours before resolution remain the key variables for traders.
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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