Recent warm-air advection across eastern Japan, driven by a strengthening southerly flow ahead of an approaching high-pressure ridge, has pushed Japan Meteorological Agency forecast models toward a daily maximum of 27°C or higher in Tokyo on May 19. Ensemble guidance shows limited spread around this threshold, with only modest cooling risk from scattered cloud cover or brief showers. This setup aligns with the market-implied 76% probability for 27°C or above, well above mid-May climatological norms of 22–24°C at the Otemachi station. Updated JMA guidance and next model runs on May 18 will further refine land-sea breeze influences and any late-day temperature adjustments before official observation.
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 19?
27°C or higher 78%
26°C 14%
25°C 5%
24°C 4%
17°C or below
<1%
18°C
<1%
19°C
<1%
20°C
1%
21°C
1%
22°C
3%
23°C
3%
24°C
4%
25°C
5%
26°C
14%
27°C or higher
78%
27°C or higher 78%
26°C 14%
25°C 5%
24°C 4%
17°C or below
<1%
18°C
<1%
19°C
<1%
20°C
1%
21°C
1%
22°C
3%
23°C
3%
24°C
4%
25°C
5%
26°C
14%
27°C or higher
78%
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 17, 2026, 12:04 AM ET
Resolution Source
https://www.wunderground.com/history/daily/jp/tokyo/RJTTThe 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.
Resolution Source
https://www.wunderground.com/history/daily/jp/tokyo/RJTTRecent warm-air advection across eastern Japan, driven by a strengthening southerly flow ahead of an approaching high-pressure ridge, has pushed Japan Meteorological Agency forecast models toward a daily maximum of 27°C or higher in Tokyo on May 19. Ensemble guidance shows limited spread around this threshold, with only modest cooling risk from scattered cloud cover or brief showers. This setup aligns with the market-implied 76% probability for 27°C or above, well above mid-May climatological norms of 22–24°C at the Otemachi station. Updated JMA guidance and next model runs on May 18 will further refine land-sea breeze influences and any late-day temperature adjustments before official observation.
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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