**Persistent rain, high humidity, and extensive cloud cover over Tokyo are anchoring overnight lows near 21–22°C for September 20, 2026, aligning with the market's leading outcomes of 22°C (46.5% implied probability) and 21°C (28.0%).** Official and ensemble forecasts from sources such as the Japan Meteorological Agency, GFS-based models, and international providers show a stalled frontal system bringing widespread precipitation and overcast skies through the weekend. This setup suppresses radiative cooling at night, with dew points remaining elevated near 21–22°C and northerly winds providing limited advection of cooler air. Model consensus points to a minimum around 22°C (roughly 72°F), with limited spread that keeps probabilities for 20°C or below modest (under 25% combined) and higher values like 23°C+ at single-digit odds. These conditions represent a modest departure from September climatology, where Tokyo's average daily minimum is near 19–20°C; the current warm, moist air mass has kept recent observed lows in the low 20s°C. With resolution just two days away and stable model guidance, trader sentiment has consolidated around the narrow 21–22°C band rather than extremes.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Tokyo on September 20?
Lowest temperature in Tokyo on September 20?
22°C 47%
21°C 29%
20°C 12%
18°C 10%
NEW
NEW
Sep 20, 2026
16°C or below
2%
17°C
2%
18°C
10%
19°C
10%
20°C
12%
21°C
29%
22°C
47%
23°C
8%
24°C
10%
25°C
7%
26°C or higher
2%
22°C 47%
21°C 29%
20°C 12%
18°C 10%
NEW
NEW
Sep 20, 2026
16°C or below
$0 Vol.
2%
17°C
$0 Vol.
2%
18°C
$0 Vol.
10%
19°C
$0 Vol.
10%
20°C
$20 Vol.
12%
21°C
$869 Vol.
29%
22°C
$197 Vol.
47%
23°C
$122 Vol.
8%
24°C
$0 Vol.
10%
25°C
$0 Vol.
7%
26°C or higher
$0 Vol.
2%
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 20 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=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, high humidity, and extensive cloud cover over Tokyo are anchoring overnight lows near 21–22°C for September 20, 2026, aligning with the market's leading outcomes of 22°C (46.5% implied probability) and 21°C (28.0%).**
Official and ensemble forecasts from sources such as the Japan Meteorological Agency, GFS-based models, and international providers show a stalled frontal system bringing widespread precipitation and overcast skies through the weekend. This setup suppresses radiative cooling at night, with dew points remaining elevated near 21–22°C and northerly winds providing limited advection of cooler air. Model consensus points to a minimum around 22°C (roughly 72°F), with limited spread that keeps probabilities for 20°C or below modest (under 25% combined) and higher values like 23°C+ at single-digit odds.
These conditions represent a modest departure from September climatology, where Tokyo's average daily minimum is near 19–20°C; the current warm, moist air mass has kept recent observed lows in the low 20s°C. With resolution just two days away and stable model guidance, trader sentiment has consolidated around the narrow 21–22°C band rather than extremes.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 20 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=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 lowest 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 18, 2026, 12:29 AM ET
Volume
$1,208End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 12:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=rjttResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 20 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=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, high humidity, and extensive cloud cover over Tokyo are anchoring overnight lows near 21–22°C for September 20, 2026, aligning with the market's leading outcomes of 22°C (46.5% implied probability) and 21°C (28.0%).**
Official and ensemble forecasts from sources such as the Japan Meteorological Agency, GFS-based models, and international providers show a stalled frontal system bringing widespread precipitation and overcast skies through the weekend. This setup suppresses radiative cooling at night, with dew points remaining elevated near 21–22°C and northerly winds providing limited advection of cooler air. Model consensus points to a minimum around 22°C (roughly 72°F), with limited spread that keeps probabilities for 20°C or below modest (under 25% combined) and higher values like 23°C+ at single-digit odds.
These conditions represent a modest departure from September climatology, where Tokyo's average daily minimum is near 19–20°C; the current warm, moist air mass has kept recent observed lows in the low 20s°C. With resolution just two days away and stable model guidance, trader sentiment has consolidated around the narrow 21–22°C band rather than extremes.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Tokyo Haneda Airport Station in degrees Celsius on 20 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=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 lowest 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
$1,208End Date
Sep 20, 2026Market Opened
Sep 18, 2026, 12:29 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=rjttResolver
0x69c47De9D...**Persistent rain, high humidity, and extensive cloud cover over Tokyo are anchoring overnight lows near 21–22°C for September 20, 2026, aligning with the market's leading outcomes of 22°C (46.5% implied probability) and 21°C (28.0%).** Official and ensemble forecasts from sources such as the Japan Meteorological Agency, GFS-based models, and international providers show a stalled frontal system bringing widespread precipitation and overcast skies through the weekend. This setup suppresses radiative cooling at night, with dew points remaining elevated near 21–22°C and northerly winds providing limited advection of cooler air. Model consensus points to a minimum around 22°C (roughly 72°F), with limited spread that keeps probabilities for 20°C or below modest (under 25% combined) and higher values like 23°C+ at single-digit odds. These conditions represent a modest departure from September climatology, where Tokyo's average daily minimum is near 19–20°C; the current warm, moist air mass has kept recent observed lows in the low 20s°C. With resolution just two days away and stable model guidance, trader sentiment has consolidated around the narrow 21–22°C band rather than extremes.
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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