Recent forecast model runs for Toronto show notable spread in the overnight low for September 19, with projected minima ranging from roughly 9–14 °C depending on cloud cover, easterly wind strength, and radiative cooling rates under partly to mostly cloudy skies. This uncertainty underpins the near-even market split between the 5 °C-or-below and 15 °C-or-higher outcomes at 46 % each, as traders weigh the potential for enhanced cooling versus persistence of mild conditions near the seasonal average low of 13 °C. Key variables include evolving high-pressure steering and any late-day moisture advection that could alter the diurnal temperature range. Updated Environment Canada and ensemble guidance expected overnight will likely narrow the distribution ahead of the close.
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 19?
Lowest temperature in Toronto on September 19?
15°C or higher 82%
5°C or below 78%
9°C 39%
13°C 39%
NEW
NEW
Sep 19, 2026
5°C or below
78%
6°C
17%
7°C
17%
8°C
17%
9°C
39%
10°C
20%
11°C
22%
12°C
32%
13°C
39%
14°C
39%
15°C or higher
82%
15°C or higher 82%
5°C or below 78%
9°C 39%
13°C 39%
NEW
NEW
Sep 19, 2026
5°C or below
$0 Vol.
78%
6°C
$0 Vol.
17%
7°C
$0 Vol.
17%
8°C
$0 Vol.
17%
9°C
$0 Vol.
39%
10°C
$0 Vol.
20%
11°C
$0 Vol.
22%
12°C
$5 Vol.
32%
13°C
$0 Vol.
39%
14°C
$0 Vol.
39%
15°C or higher
$0 Vol.
82%
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 19 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.Recent forecast model runs for Toronto show notable spread in the overnight low for September 19, with projected minima ranging from roughly 9–14 °C depending on cloud cover, easterly wind strength, and radiative cooling rates under partly to mostly cloudy skies. This uncertainty underpins the near-even market split between the 5 °C-or-below and 15 °C-or-higher outcomes at 46 % each, as traders weigh the potential for enhanced cooling versus persistence of mild conditions near the seasonal average low of 13 °C. Key variables include evolving high-pressure steering and any late-day moisture advection that could alter the diurnal temperature range. Updated Environment Canada and ensemble guidance expected overnight will likely narrow the distribution ahead of the close.
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 19 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 17, 2026, 8:29 AM ET
Volume
$5End Date
Sep 19, 2026Market Opened
Sep 17, 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 19 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.Recent forecast model runs for Toronto show notable spread in the overnight low for September 19, with projected minima ranging from roughly 9–14 °C depending on cloud cover, easterly wind strength, and radiative cooling rates under partly to mostly cloudy skies. This uncertainty underpins the near-even market split between the 5 °C-or-below and 15 °C-or-higher outcomes at 46 % each, as traders weigh the potential for enhanced cooling versus persistence of mild conditions near the seasonal average low of 13 °C. Key variables include evolving high-pressure steering and any late-day moisture advection that could alter the diurnal temperature range. Updated Environment Canada and ensemble guidance expected overnight will likely narrow the distribution ahead of the close.
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 19 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
$5End Date
Sep 19, 2026Market Opened
Sep 17, 2026, 8:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=cyyzResolver
0x69c47De9D...Recent forecast model runs for Toronto show notable spread in the overnight low for September 19, with projected minima ranging from roughly 9–14 °C depending on cloud cover, easterly wind strength, and radiative cooling rates under partly to mostly cloudy skies. This uncertainty underpins the near-even market split between the 5 °C-or-below and 15 °C-or-higher outcomes at 46 % each, as traders weigh the potential for enhanced cooling versus persistence of mild conditions near the seasonal average low of 13 °C. Key variables include evolving high-pressure steering and any late-day moisture advection that could alter the diurnal temperature range. Updated Environment Canada and ensemble guidance expected overnight will likely narrow the distribution ahead of the close.
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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