Recent model consensus from ECMWF, GFS, and Finnish Meteorological Institute guidance points to overnight lows near 12°C in Helsinki on September 18 under persistent southwesterly flow, widespread cloud cover, and periods of rain that limit radiative cooling. These mild maritime conditions, well above the long-term September average low of roughly 9°C, explain why higher outcomes hold limited market share, while the tight clustering between 10°C and 11°C reflects modest ensemble spread in the exact timing of any clearer intervals that could permit an extra degree of cooling. Traders appear to weigh the risk that localized breaks in cloud or slightly stronger advection could nudge the minimum down to the 10–11°C band, with resolution hinging on the final observed reading from official stations.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedLowest temperature in Helsinki on September 18?
Lowest temperature in Helsinki on September 18?
15°C or higher 81%
9°C 40%
8°C 39%
11°C 32%
NEW
NEW
Sep 18, 2026
5°C or below
2%
6°C
6%
7°C
17%
8°C
39%
9°C
40%
10°C
31%
11°C
32%
12°C
28%
13°C
15%
14°C
14%
15°C or higher
81%
15°C or higher 81%
9°C 40%
8°C 39%
11°C 32%
NEW
NEW
Sep 18, 2026
5°C or below
$0 Vol.
2%
6°C
$0 Vol.
6%
7°C
$0 Vol.
17%
8°C
$0 Vol.
39%
9°C
$0 Vol.
40%
10°C
$0 Vol.
31%
11°C
$6 Vol.
32%
12°C
$0 Vol.
28%
13°C
$0 Vol.
15%
14°C
$0 Vol.
14%
15°C or higher
$0 Vol.
81%
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Helsinki Vantaa 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=efhk
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 model consensus from ECMWF, GFS, and Finnish Meteorological Institute guidance points to overnight lows near 12°C in Helsinki on September 18 under persistent southwesterly flow, widespread cloud cover, and periods of rain that limit radiative cooling. These mild maritime conditions, well above the long-term September average low of roughly 9°C, explain why higher outcomes hold limited market share, while the tight clustering between 10°C and 11°C reflects modest ensemble spread in the exact timing of any clearer intervals that could permit an extra degree of cooling. Traders appear to weigh the risk that localized breaks in cloud or slightly stronger advection could nudge the minimum down to the 10–11°C band, with resolution hinging on the final observed reading from official stations.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Helsinki Vantaa 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=efhk
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=efhk
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, 12:31 AM ET
Volume
$6End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:31 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Helsinki Vantaa 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=efhk
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 model consensus from ECMWF, GFS, and Finnish Meteorological Institute guidance points to overnight lows near 12°C in Helsinki on September 18 under persistent southwesterly flow, widespread cloud cover, and periods of rain that limit radiative cooling. These mild maritime conditions, well above the long-term September average low of roughly 9°C, explain why higher outcomes hold limited market share, while the tight clustering between 10°C and 11°C reflects modest ensemble spread in the exact timing of any clearer intervals that could permit an extra degree of cooling. Traders appear to weigh the risk that localized breaks in cloud or slightly stronger advection could nudge the minimum down to the 10–11°C band, with resolution hinging on the final observed reading from official stations.
This market will resolve to the temperature range that contains the lowest temperature recorded by NOAA at the Helsinki Vantaa 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=efhk
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=efhk
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
$6End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:31 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...Recent model consensus from ECMWF, GFS, and Finnish Meteorological Institute guidance points to overnight lows near 12°C in Helsinki on September 18 under persistent southwesterly flow, widespread cloud cover, and periods of rain that limit radiative cooling. These mild maritime conditions, well above the long-term September average low of roughly 9°C, explain why higher outcomes hold limited market share, while the tight clustering between 10°C and 11°C reflects modest ensemble spread in the exact timing of any clearer intervals that could permit an extra degree of cooling. Traders appear to weigh the risk that localized breaks in cloud or slightly stronger advection could nudge the minimum down to the 10–11°C band, with resolution hinging on the final observed reading from official stations.
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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