Official Environment Canada guidance projects a 20°C high for Toronto on September 20, featuring morning showers with 60% probability, followed by clearing skies and northeast winds gusting to 40 km/h. Multiple numerical models converge near this value, though slight differences in cloud timing and boundary-layer mixing produce a modest spread that supports 21°C outcomes in some runs. Traders assign the highest implied probabilities to 20°C and 21°C, reflecting uncertainty in peak solar heating under variable cloud cover rather than any major synoptic shift. Lower probabilities for 22°C or above align with the limited warming potential from the current airmass and persistent onshore flow. Updated model guidance and afternoon observations will refine the exact maximum before market 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 20?
Highest temperature in Toronto on September 20?
21°C 39%
20°C 31%
19°C 17%
22°C or higher 16%
NEW
$10,836 Vol.
NEW
$10,836 Vol.
Sep 20, 2026
12°C or below
<1%
13°C
<1%
14°C
<1%
15°C
<1%
16°C
<1%
17°C
<1%
18°C
2%
19°C
17%
20°C
31%
21°C
39%
22°C or higher
16%
21°C 39%
20°C 31%
19°C 17%
22°C or higher 16%
NEW
$10,836 Vol.
NEW
$10,836 Vol.
Sep 20, 2026
12°C or below
$120 Vol.
<1%
13°C
$120 Vol.
<1%
14°C
$120 Vol.
<1%
15°C
$120 Vol.
<1%
16°C
$243 Vol.
<1%
17°C
$619 Vol.
<1%
18°C
$1,183 Vol.
2%
19°C
$1,832 Vol.
17%
20°C
$1,437 Vol.
31%
21°C
$3,101 Vol.
39%
22°C or higher
$1,942 Vol.
16%
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 20 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.Official Environment Canada guidance projects a 20°C high for Toronto on September 20, featuring morning showers with 60% probability, followed by clearing skies and northeast winds gusting to 40 km/h. Multiple numerical models converge near this value, though slight differences in cloud timing and boundary-layer mixing produce a modest spread that supports 21°C outcomes in some runs. Traders assign the highest implied probabilities to 20°C and 21°C, reflecting uncertainty in peak solar heating under variable cloud cover rather than any major synoptic shift. Lower probabilities for 22°C or above align with the limited warming potential from the current airmass and persistent onshore flow. Updated model guidance and afternoon observations will refine the exact maximum before market 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 20 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 18, 2026, 8:56 AM ET
Volume
$10,836End Date
Sep 20, 2026Market Opened
Sep 18, 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 20 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.Official Environment Canada guidance projects a 20°C high for Toronto on September 20, featuring morning showers with 60% probability, followed by clearing skies and northeast winds gusting to 40 km/h. Multiple numerical models converge near this value, though slight differences in cloud timing and boundary-layer mixing produce a modest spread that supports 21°C outcomes in some runs. Traders assign the highest implied probabilities to 20°C and 21°C, reflecting uncertainty in peak solar heating under variable cloud cover rather than any major synoptic shift. Lower probabilities for 22°C or above align with the limited warming potential from the current airmass and persistent onshore flow. Updated model guidance and afternoon observations will refine the exact maximum before market 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 20 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
$10,836End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Official Environment Canada guidance projects a 20°C high for Toronto on September 20, featuring morning showers with 60% probability, followed by clearing skies and northeast winds gusting to 40 km/h. Multiple numerical models converge near this value, though slight differences in cloud timing and boundary-layer mixing produce a modest spread that supports 21°C outcomes in some runs. Traders assign the highest implied probabilities to 20°C and 21°C, reflecting uncertainty in peak solar heating under variable cloud cover rather than any major synoptic shift. Lower probabilities for 22°C or above align with the limited warming potential from the current airmass and persistent onshore flow. Updated model guidance and afternoon observations will refine the exact maximum before market 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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