Recent Environment Canada and numerical model guidance indicate a high near 20–22°C for Toronto on September 20, driven by northeasterly flow off Lake Ontario that limits daytime heating while maintaining cloud cover and a modest chance of light showers. Persistent onshore winds and mid-level moisture are keeping maximum temperatures close to seasonal norms around the long-term average of 21°C, with limited diurnal range expected under mostly cloudy skies. Small differences in forecast high hinge on the exact timing of any breaks in cloud or shower development, which official updates from Environment Canada and short-range model runs will clarify over the next 48 hours. Trader odds reflect this tight clustering of guidance, with outcomes separated by only a degree or two.
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?
20°C 30%
21°C 29%
22°C or higher 24%
19°C 19%
NEW
NEW
Sep 20, 2026
12°C or below
5%
13°C
5%
14°C
7%
15°C
7%
16°C
5%
17°C
4%
18°C
11%
19°C
19%
20°C
30%
21°C
29%
22°C or higher
24%
20°C 30%
21°C 29%
22°C or higher 24%
19°C 19%
NEW
NEW
Sep 20, 2026
12°C or below
$10 Vol.
5%
13°C
$10 Vol.
5%
14°C
$10 Vol.
7%
15°C
$10 Vol.
7%
16°C
$4 Vol.
5%
17°C
$0 Vol.
4%
18°C
$0 Vol.
11%
19°C
$0 Vol.
19%
20°C
$0 Vol.
30%
21°C
$0 Vol.
29%
22°C or higher
$5 Vol.
24%
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.Recent Environment Canada and numerical model guidance indicate a high near 20–22°C for Toronto on September 20, driven by northeasterly flow off Lake Ontario that limits daytime heating while maintaining cloud cover and a modest chance of light showers. Persistent onshore winds and mid-level moisture are keeping maximum temperatures close to seasonal norms around the long-term average of 21°C, with limited diurnal range expected under mostly cloudy skies. Small differences in forecast high hinge on the exact timing of any breaks in cloud or shower development, which official updates from Environment Canada and short-range model runs will clarify over the next 48 hours. Trader odds reflect this tight clustering of guidance, with outcomes separated by only a degree or two.
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
$49End 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.Recent Environment Canada and numerical model guidance indicate a high near 20–22°C for Toronto on September 20, driven by northeasterly flow off Lake Ontario that limits daytime heating while maintaining cloud cover and a modest chance of light showers. Persistent onshore winds and mid-level moisture are keeping maximum temperatures close to seasonal norms around the long-term average of 21°C, with limited diurnal range expected under mostly cloudy skies. Small differences in forecast high hinge on the exact timing of any breaks in cloud or shower development, which official updates from Environment Canada and short-range model runs will clarify over the next 48 hours. Trader odds reflect this tight clustering of guidance, with outcomes separated by only a degree or two.
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
$49End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Recent Environment Canada and numerical model guidance indicate a high near 20–22°C for Toronto on September 20, driven by northeasterly flow off Lake Ontario that limits daytime heating while maintaining cloud cover and a modest chance of light showers. Persistent onshore winds and mid-level moisture are keeping maximum temperatures close to seasonal norms around the long-term average of 21°C, with limited diurnal range expected under mostly cloudy skies. Small differences in forecast high hinge on the exact timing of any breaks in cloud or shower development, which official updates from Environment Canada and short-range model runs will clarify over the next 48 hours. Trader odds reflect this tight clustering of guidance, with outcomes separated by only a degree or two.
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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