Persistent rain and extensive cloud cover from an active frontal system are suppressing daytime heating in Tokyo, positioning 24–26°C as the leading market-implied outcomes for the September 21 maximum temperature. Official Japan Meteorological Agency guidance and ensemble forecasts indicate heavy precipitation and overcast skies through Monday, with high humidity and northeasterly flow limiting insolation and keeping surface temperatures near or below seasonal normals around 25–26°C. Recent model runs show limited warming potential even if rain eases slightly, consistent with the 35% and 24.5% probabilities assigned to 25°C and 26°C. Updated short-range guidance expected before resolution could refine the exact peak if breaks in cloud cover emerge.
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 September 21?
Highest temperature in Tokyo on September 21?
25°C 35%
24°C 28%
26°C 25%
27°C 12%
NEW
NEW
Sep 21, 2026
20°C or below
<1%
21°C
1%
22°C
5%
23°C
11%
24°C
27%
25°C
35%
26°C
25%
27°C
12%
28°C
6%
29°C
4%
30°C or higher
2%
25°C 35%
24°C 28%
26°C 25%
27°C 12%
NEW
NEW
Sep 21, 2026
20°C or below
$111 Vol.
<1%
21°C
$271 Vol.
1%
22°C
$133 Vol.
5%
23°C
$314 Vol.
11%
24°C
$766 Vol.
27%
25°C
$489 Vol.
35%
26°C
$343 Vol.
25%
27°C
$159 Vol.
12%
28°C
$93 Vol.
6%
29°C
$181 Vol.
4%
30°C or higher
$385 Vol.
2%
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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.Persistent rain and extensive cloud cover from an active frontal system are suppressing daytime heating in Tokyo, positioning 24–26°C as the leading market-implied outcomes for the September 21 maximum temperature. Official Japan Meteorological Agency guidance and ensemble forecasts indicate heavy precipitation and overcast skies through Monday, with high humidity and northeasterly flow limiting insolation and keeping surface temperatures near or below seasonal normals around 25–26°C. Recent model runs show limited warming potential even if rain eases slightly, consistent with the 35% and 24.5% probabilities assigned to 25°C and 26°C. Updated short-range guidance expected before resolution could refine the exact peak if breaks in cloud cover emerge.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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 highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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 19, 2026, 12:56 AM ET
Volume
$3,244End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 12:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=rjttResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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.Persistent rain and extensive cloud cover from an active frontal system are suppressing daytime heating in Tokyo, positioning 24–26°C as the leading market-implied outcomes for the September 21 maximum temperature. Official Japan Meteorological Agency guidance and ensemble forecasts indicate heavy precipitation and overcast skies through Monday, with high humidity and northeasterly flow limiting insolation and keeping surface temperatures near or below seasonal normals around 25–26°C. Recent model runs show limited warming potential even if rain eases slightly, consistent with the 35% and 24.5% probabilities assigned to 25°C and 26°C. Updated short-range guidance expected before resolution could refine the exact peak if breaks in cloud cover emerge.
This market will resolve to the temperature range that contains the highest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 21 Sep '26.
The resolution source for this market will be information from NOAA, specifically the highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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 highest reading under the "Temp" column for all times on this day, available here: https://www.weather.gov/wrh/timeseries?site=rjtt
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
$3,244End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 12:56 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=rjttResolver
0x69c47De9D...Persistent rain and extensive cloud cover from an active frontal system are suppressing daytime heating in Tokyo, positioning 24–26°C as the leading market-implied outcomes for the September 21 maximum temperature. Official Japan Meteorological Agency guidance and ensemble forecasts indicate heavy precipitation and overcast skies through Monday, with high humidity and northeasterly flow limiting insolation and keeping surface temperatures near or below seasonal normals around 25–26°C. Recent model runs show limited warming potential even if rain eases slightly, consistent with the 35% and 24.5% probabilities assigned to 25°C and 26°C. Updated short-range guidance expected before resolution could refine the exact peak if breaks in cloud cover emerge.
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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