Recent model consensus from the Japan Meteorological Agency and global ensembles points to warm southerly flow and abundant sunshine driving Tokyo’s maximum temperature to 28 °C or higher on May 18. A persistent high-pressure ridge over the western Pacific is promoting subsidence and reduced cloud cover, while sea-surface temperatures around the Kanto region remain above the May climatological mean, enhancing boundary-layer warming. These conditions mirror the setup that produced the 30.5 °C reading earlier in the month, pushing the market-implied probability for 28 °C or above to 75.5 %. Updated 12–36 h forecasts issued later today will refine the exact peak, with any shift in the steering flow or increased moisture the primary variables that could cap the high near 27 °C.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Tokyo on May 18?
Highest temperature in Tokyo on May 18?
28°C or higher 76%
27°C 20%
26°C 5.8%
25°C <1%
NEW
$39,625 Vol.
NEW
$39,625 Vol.
May 18, 2026
18°C or below
<1%
19°C
<1%
20°C
<1%
21°C
<1%
22°C
<1%
23°C
<1%
24°C
1%
25°C
1%
26°C
6%
27°C
20%
28°C or higher
76%
28°C or higher 76%
27°C 20%
26°C 5.8%
25°C <1%
NEW
$39,625 Vol.
NEW
$39,625 Vol.
May 18, 2026
18°C or below
$3,106 Vol.
<1%
19°C
$1,432 Vol.
<1%
20°C
$1,081 Vol.
<1%
21°C
$1,264 Vol.
<1%
22°C
$1,918 Vol.
<1%
23°C
$2,398 Vol.
<1%
24°C
$15,812 Vol.
1%
25°C
$3,509 Vol.
1%
26°C
$3,294 Vol.
6%
27°C
$2,289 Vol.
20%
28°C or higher
$3,627 Vol.
76%
This market will resolve to the temperature range that contains the highest temperature recorded at the Tokyo Haneda Airport Station in degrees Celsius on 18 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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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 model consensus from the Japan Meteorological Agency and global ensembles points to warm southerly flow and abundant sunshine driving Tokyo’s maximum temperature to 28 °C or higher on May 18. A persistent high-pressure ridge over the western Pacific is promoting subsidence and reduced cloud cover, while sea-surface temperatures around the Kanto region remain above the May climatological mean, enhancing boundary-layer warming. These conditions mirror the setup that produced the 30.5 °C reading earlier in the month, pushing the market-implied probability for 28 °C or above to 75.5 %. Updated 12–36 h forecasts issued later today will refine the exact peak, with any shift in the steering flow or increased moisture the primary variables that could cap the high near 27 °C.
This market will resolve to the temperature range that contains the highest temperature recorded at the Tokyo Haneda Airport Station in degrees Celsius on 18 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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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 16, 2026, 12:04 AM ET
Volume
$39,625End Date
May 18, 2026Market Opened
May 16, 2026, 12:04 AM ETResolution Source
https://www.wunderground.com/history/daily/jp/tokyo/RJTTThis market will resolve to the temperature range that contains the highest temperature recorded at the Tokyo Haneda Airport Station in degrees Celsius on 18 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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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 model consensus from the Japan Meteorological Agency and global ensembles points to warm southerly flow and abundant sunshine driving Tokyo’s maximum temperature to 28 °C or higher on May 18. A persistent high-pressure ridge over the western Pacific is promoting subsidence and reduced cloud cover, while sea-surface temperatures around the Kanto region remain above the May climatological mean, enhancing boundary-layer warming. These conditions mirror the setup that produced the 30.5 °C reading earlier in the month, pushing the market-implied probability for 28 °C or above to 75.5 %. Updated 12–36 h forecasts issued later today will refine the exact peak, with any shift in the steering flow or increased moisture the primary variables that could cap the high near 27 °C.
This market will resolve to the temperature range that contains the highest temperature recorded at the Tokyo Haneda Airport Station in degrees Celsius on 18 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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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 Tokyo Haneda Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/jp/tokyo/RJTT.
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
$39,625End Date
May 18, 2026Market Opened
May 16, 2026, 12:04 AM ETResolution Source
https://www.wunderground.com/history/daily/jp/tokyo/RJTTRecent model consensus from the Japan Meteorological Agency and global ensembles points to warm southerly flow and abundant sunshine driving Tokyo’s maximum temperature to 28 °C or higher on May 18. A persistent high-pressure ridge over the western Pacific is promoting subsidence and reduced cloud cover, while sea-surface temperatures around the Kanto region remain above the May climatological mean, enhancing boundary-layer warming. These conditions mirror the setup that produced the 30.5 °C reading earlier in the month, pushing the market-implied probability for 28 °C or above to 75.5 %. Updated 12–36 h forecasts issued later today will refine the exact peak, with any shift in the steering flow or increased moisture the primary variables that could cap the high near 27 °C.
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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