Recent forecasts from Environment Canada and other models indicate a high near 20°C for Toronto on September 20, with northeast winds, increasing cloud cover, and a chance of showers keeping daytime maxima modest amid mild autumn conditions. This aligns with the closely matched market-implied odds favoring 20°C or 21°C, as subtle differences in cloud timing, precipitation onset, or boundary-layer mixing can shift the peak by 1–2°C. Historical September averages near 21°C provide context, yet current guidance highlights limited warming potential due to onshore flow and reduced insolation. Updated model runs and official observations through the morning will likely refine resolution criteria for the daily maximum.
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 35%
21°C 28%
19°C 20%
22°C or higher 11%
NEW
NEW
Sep 20, 2026
12°C or below
<1%
13°C
<1%
14°C
<1%
15°C
<1%
16°C
<1%
17°C
3%
18°C
6%
19°C
22%
20°C
35%
21°C
28%
22°C or higher
11%
20°C 35%
21°C 28%
19°C 20%
22°C or higher 11%
NEW
NEW
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
$213 Vol.
<1%
17°C
$238 Vol.
3%
18°C
$256 Vol.
6%
19°C
$296 Vol.
22%
20°C
$111 Vol.
35%
21°C
$137 Vol.
28%
22°C or higher
$740 Vol.
11%
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 forecasts from Environment Canada and other models indicate a high near 20°C for Toronto on September 20, with northeast winds, increasing cloud cover, and a chance of showers keeping daytime maxima modest amid mild autumn conditions. This aligns with the closely matched market-implied odds favoring 20°C or 21°C, as subtle differences in cloud timing, precipitation onset, or boundary-layer mixing can shift the peak by 1–2°C. Historical September averages near 21°C provide context, yet current guidance highlights limited warming potential due to onshore flow and reduced insolation. Updated model runs and official observations through the morning will likely refine resolution criteria for the daily maximum.
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
$2,405End 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 forecasts from Environment Canada and other models indicate a high near 20°C for Toronto on September 20, with northeast winds, increasing cloud cover, and a chance of showers keeping daytime maxima modest amid mild autumn conditions. This aligns with the closely matched market-implied odds favoring 20°C or 21°C, as subtle differences in cloud timing, precipitation onset, or boundary-layer mixing can shift the peak by 1–2°C. Historical September averages near 21°C provide context, yet current guidance highlights limited warming potential due to onshore flow and reduced insolation. Updated model runs and official observations through the morning will likely refine resolution criteria for the daily maximum.
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
$2,405End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 8:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Recent forecasts from Environment Canada and other models indicate a high near 20°C for Toronto on September 20, with northeast winds, increasing cloud cover, and a chance of showers keeping daytime maxima modest amid mild autumn conditions. This aligns with the closely matched market-implied odds favoring 20°C or 21°C, as subtle differences in cloud timing, precipitation onset, or boundary-layer mixing can shift the peak by 1–2°C. Historical September averages near 21°C provide context, yet current guidance highlights limited warming potential due to onshore flow and reduced insolation. Updated model runs and official observations through the morning will likely refine resolution criteria for the daily maximum.
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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