**Official forecasts from Environment Canada position a 14°C overnight low as the most likely minimum for Toronto on September 18, 2026, driving the 45.5% market-implied probability.** Sunny daytime conditions with a high near 22°C followed by increasing cloud cover and northerly winds at 10–15 km/h should limit daytime heating while permitting moderate radiative cooling overnight. Model consensus across regional guidance shows lows clustered between 13–15°C, consistent with early-fall climatology when Toronto’s average September minimum falls around 12–14°C. The 26.5% odds on 8°C or below or 18°C or higher reflect residual uncertainty in cloud cover timing and wind strength, which can alter cooling rates by several degrees. Updated model runs and Environment Canada’s next briefing will refine these probabilities ahead of the overnight period.
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 18?
Lowest temperature in Toronto on September 18?
8°C or below 54%
18°C or higher 54%
14°C 45%
9°C 39%
NEW
NEW
Sep 18, 2026
8°C or below
54%
9°C
39%
10°C
39%
11°C
39%
12°C
39%
13°C
39%
14°C
45%
15°C
22%
16°C
22%
17°C
39%
18°C or higher
54%
8°C or below 54%
18°C or higher 54%
14°C 45%
9°C 39%
NEW
NEW
Sep 18, 2026
8°C or below
$0 Vol.
54%
9°C
$0 Vol.
39%
10°C
$0 Vol.
39%
11°C
$0 Vol.
39%
12°C
$0 Vol.
39%
13°C
$0 Vol.
39%
14°C
$12 Vol.
45%
15°C
$0 Vol.
22%
16°C
$0 Vol.
22%
17°C
$0 Vol.
39%
18°C or higher
$0 Vol.
54%
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 18 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.**Official forecasts from Environment Canada position a 14°C overnight low as the most likely minimum for Toronto on September 18, 2026, driving the 45.5% market-implied probability.** Sunny daytime conditions with a high near 22°C followed by increasing cloud cover and northerly winds at 10–15 km/h should limit daytime heating while permitting moderate radiative cooling overnight. Model consensus across regional guidance shows lows clustered between 13–15°C, consistent with early-fall climatology when Toronto’s average September minimum falls around 12–14°C. The 26.5% odds on 8°C or below or 18°C or higher reflect residual uncertainty in cloud cover timing and wind strength, which can alter cooling rates by several degrees. Updated model runs and Environment Canada’s next briefing will refine these probabilities ahead of the overnight period.
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 18 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 16, 2026, 8:29 AM ET
Volume
$12End Date
Sep 18, 2026Market Opened
Sep 16, 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 18 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.**Official forecasts from Environment Canada position a 14°C overnight low as the most likely minimum for Toronto on September 18, 2026, driving the 45.5% market-implied probability.** Sunny daytime conditions with a high near 22°C followed by increasing cloud cover and northerly winds at 10–15 km/h should limit daytime heating while permitting moderate radiative cooling overnight. Model consensus across regional guidance shows lows clustered between 13–15°C, consistent with early-fall climatology when Toronto’s average September minimum falls around 12–14°C. The 26.5% odds on 8°C or below or 18°C or higher reflect residual uncertainty in cloud cover timing and wind strength, which can alter cooling rates by several degrees. Updated model runs and Environment Canada’s next briefing will refine these probabilities ahead of the overnight period.
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 18 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
$12End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...**Official forecasts from Environment Canada position a 14°C overnight low as the most likely minimum for Toronto on September 18, 2026, driving the 45.5% market-implied probability.** Sunny daytime conditions with a high near 22°C followed by increasing cloud cover and northerly winds at 10–15 km/h should limit daytime heating while permitting moderate radiative cooling overnight. Model consensus across regional guidance shows lows clustered between 13–15°C, consistent with early-fall climatology when Toronto’s average September minimum falls around 12–14°C. The 26.5% odds on 8°C or below or 18°C or higher reflect residual uncertainty in cloud cover timing and wind strength, which can alter cooling rates by several degrees. Updated model runs and Environment Canada’s next briefing will refine these probabilities ahead of the overnight period.
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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