Recent forecasts from Environment Canada and ensemble models indicate a warm, humid air mass with southerly flow and increasing cloud cover ahead of a frontal system, keeping overnight minimums near 19–20 °C for Toronto on September 9. Widespread showers and thunderstorms expected during the day will limit daytime heating and reduce nocturnal radiative cooling, supporting the market’s tight clustering around these values. Higher outcomes near 24 °C would require clearer skies and stronger mixing than currently projected, while colder readings below 18 °C remain unlikely absent an unexpected cold-air intrusion. Updated model runs overnight and morning observations will refine the exact minimum before the market resolves.
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 9?
24°C or higher 54%
19°C 37%
20°C 28%
18°C 28%
14°C or below
8%
15°C
11%
16°C
12%
17°C
14%
18°C
28%
19°C
37%
20°C
28%
21°C
24%
22°C
18%
23°C
14%
24°C or higher
54%
24°C or higher 54%
19°C 37%
20°C 28%
18°C 28%
14°C or below
8%
15°C
11%
16°C
12%
17°C
14%
18°C
28%
19°C
37%
20°C
28%
21°C
24%
22°C
18%
23°C
14%
24°C or higher
54%
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 7, 2026, 8:29 AM ET
Resolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...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.
Resolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Recent forecasts from Environment Canada and ensemble models indicate a warm, humid air mass with southerly flow and increasing cloud cover ahead of a frontal system, keeping overnight minimums near 19–20 °C for Toronto on September 9. Widespread showers and thunderstorms expected during the day will limit daytime heating and reduce nocturnal radiative cooling, supporting the market’s tight clustering around these values. Higher outcomes near 24 °C would require clearer skies and stronger mixing than currently projected, while colder readings below 18 °C remain unlikely absent an unexpected cold-air intrusion. Updated model runs overnight and morning observations will refine the exact minimum before the market resolves.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
Beware of external links.
Beware of external links.
Frequently Asked Questions