**Recent ensemble forecasts and official guidance from the Japan Meteorological Agency point to an overnight low near 19°C in Tokyo on September 18, driven by extensive cloud cover limiting radiative cooling and moderate northerly winds promoting mixing.** Models show persistent overcast conditions following several days of rain, with surface pressures around 1020–1023 hPa supporting stable but not strongly cooling air masses. Slight variations in the exact minimum hinge on the timing of any partial clearing or wind gust strength overnight, which explains the near-even market split between 19°C and 20°C implied probabilities. Historical September baselines for Tokyo lows average near 19–20°C, providing context for why traders see these two outcomes as the most probable under current synoptic patterns. Updated model runs and JMA briefings remain the key near-term catalysts for any shifts.
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 18?
Lowest temperature in Tokyo on September 18?
20°C 43%
19°C 36%
22°C 15%
21°C 13%
NEW
NEW
Sep 18, 2026
14°C or below
1%
15°C
1%
16°C
<1%
17°C
8%
18°C
8%
19°C
36%
20°C
43%
21°C
13%
22°C
15%
23°C
5%
24°C or higher
1%
20°C 43%
19°C 36%
22°C 15%
21°C 13%
NEW
NEW
Sep 18, 2026
14°C or below
$53 Vol.
1%
15°C
$53 Vol.
1%
16°C
$0 Vol.
<1%
17°C
$0 Vol.
8%
18°C
$243 Vol.
8%
19°C
$1,426 Vol.
36%
20°C
$1,029 Vol.
43%
21°C
$16 Vol.
13%
22°C
$0 Vol.
15%
23°C
$0 Vol.
5%
24°C or higher
$29 Vol.
1%
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 18 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.**Recent ensemble forecasts and official guidance from the Japan Meteorological Agency point to an overnight low near 19°C in Tokyo on September 18, driven by extensive cloud cover limiting radiative cooling and moderate northerly winds promoting mixing.**
Models show persistent overcast conditions following several days of rain, with surface pressures around 1020–1023 hPa supporting stable but not strongly cooling air masses. Slight variations in the exact minimum hinge on the timing of any partial clearing or wind gust strength overnight, which explains the near-even market split between 19°C and 20°C implied probabilities. Historical September baselines for Tokyo lows average near 19–20°C, providing context for why traders see these two outcomes as the most probable under current synoptic patterns. Updated model runs and JMA briefings remain the key near-term catalysts for any shifts.
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 18 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 16, 2026, 12:30 AM ET
Volume
$2,832End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:30 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 18 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.**Recent ensemble forecasts and official guidance from the Japan Meteorological Agency point to an overnight low near 19°C in Tokyo on September 18, driven by extensive cloud cover limiting radiative cooling and moderate northerly winds promoting mixing.**
Models show persistent overcast conditions following several days of rain, with surface pressures around 1020–1023 hPa supporting stable but not strongly cooling air masses. Slight variations in the exact minimum hinge on the timing of any partial clearing or wind gust strength overnight, which explains the near-even market split between 19°C and 20°C implied probabilities. Historical September baselines for Tokyo lows average near 19–20°C, providing context for why traders see these two outcomes as the most probable under current synoptic patterns. Updated model runs and JMA briefings remain the key near-term catalysts for any shifts.
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 18 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
$2,832End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:30 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=rjttResolver
0x69c47De9D...**Recent ensemble forecasts and official guidance from the Japan Meteorological Agency point to an overnight low near 19°C in Tokyo on September 18, driven by extensive cloud cover limiting radiative cooling and moderate northerly winds promoting mixing.** Models show persistent overcast conditions following several days of rain, with surface pressures around 1020–1023 hPa supporting stable but not strongly cooling air masses. Slight variations in the exact minimum hinge on the timing of any partial clearing or wind gust strength overnight, which explains the near-even market split between 19°C and 20°C implied probabilities. Historical September baselines for Tokyo lows average near 19–20°C, providing context for why traders see these two outcomes as the most probable under current synoptic patterns. Updated model runs and JMA briefings remain the key near-term catalysts for any shifts.
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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