Recent short-range ensemble forecasts from Environment and Climate Change Canada and global numerical weather prediction models show Toronto’s May 19 maximum temperature most likely falling between 27 °C and 30 °C, producing the tight clustering of market-implied odds around those values. Day-to-day differences in cloud cover, surface wind speed, and the timing of any passing frontal boundary determine whether peak heating reaches the upper or lower end of that range; stronger insolation and lighter winds favor 29–30 °C, while increased moisture or earlier cloud build-up keeps readings nearer 27–28 °C. With only two days remaining, the next 00Z and 12Z model cycles will narrow the uncertainty and are expected to drive the final shifts in trader positions before resolution.
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 May 19?
Highest temperature in Toronto on May 19?
29°C 30%
28°C 26%
27°C 20%
30°C 16%
NEW
NEW
May 19, 2026
22°C or below
<1%
23°C
<1%
24°C
<1%
25°C
2%
26°C
5%
27°C
20%
28°C
26%
29°C
30%
30°C
16%
31°C
8%
32°C or higher
4%
29°C 30%
28°C 26%
27°C 20%
30°C 16%
NEW
NEW
May 19, 2026
22°C or below
$571 Vol.
<1%
23°C
$367 Vol.
<1%
24°C
$498 Vol.
<1%
25°C
$77 Vol.
2%
26°C
$90 Vol.
5%
27°C
$196 Vol.
20%
28°C
$50 Vol.
26%
29°C
$99 Vol.
30%
30°C
$97 Vol.
16%
31°C
$31 Vol.
8%
32°C or higher
$64 Vol.
4%
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Recent short-range ensemble forecasts from Environment and Climate Change Canada and global numerical weather prediction models show Toronto’s May 19 maximum temperature most likely falling between 27 °C and 30 °C, producing the tight clustering of market-implied odds around those values. Day-to-day differences in cloud cover, surface wind speed, and the timing of any passing frontal boundary determine whether peak heating reaches the upper or lower end of that range; stronger insolation and lighter winds favor 29–30 °C, while increased moisture or earlier cloud build-up keeps readings nearer 27–28 °C. With only two days remaining, the next 00Z and 12Z model cycles will narrow the uncertainty and are expected to drive the final shifts in trader positions before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: May 17, 2026, 12:03 AM ET
Volume
$2,143End Date
May 19, 2026Market Opened
May 17, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZThis market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Recent short-range ensemble forecasts from Environment and Climate Change Canada and global numerical weather prediction models show Toronto’s May 19 maximum temperature most likely falling between 27 °C and 30 °C, producing the tight clustering of market-implied odds around those values. Day-to-day differences in cloud cover, surface wind speed, and the timing of any passing frontal boundary determine whether peak heating reaches the upper or lower end of that range; stronger insolation and lighter winds favor 29–30 °C, while increased moisture or earlier cloud build-up keeps readings nearer 27–28 °C. With only two days remaining, the next 00Z and 12Z model cycles will narrow the uncertainty and are expected to drive the final shifts in trader positions before resolution.
This market will resolve to the temperature range that contains the highest temperature recorded at the Toronto Pearson Intl Airport Station in degrees Celsius on 19 May '26.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Toronto Pearson Intl Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/ca/mississauga/CYYZ.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
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.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$2,143End Date
May 19, 2026Market Opened
May 17, 2026, 12:03 AM ETResolution Source
https://www.wunderground.com/history/daily/ca/mississauga/CYYZRecent short-range ensemble forecasts from Environment and Climate Change Canada and global numerical weather prediction models show Toronto’s May 19 maximum temperature most likely falling between 27 °C and 30 °C, producing the tight clustering of market-implied odds around those values. Day-to-day differences in cloud cover, surface wind speed, and the timing of any passing frontal boundary determine whether peak heating reaches the upper or lower end of that range; stronger insolation and lighter winds favor 29–30 °C, while increased moisture or earlier cloud build-up keeps readings nearer 27–28 °C. With only two days remaining, the next 00Z and 12Z model cycles will narrow the uncertainty and are expected to drive the final shifts in trader positions before resolution.
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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