**Forecast models from sources like the Finnish Meteorological Institute, Yr.no, and GFS-based outlooks currently indicate a highest temperature in Helsinki on September 18 most likely between 14–16°C.** Southwesterly flow, persistent cloud cover, and periods of light rain or showers are expected to limit daytime heating, keeping maxima near or slightly above seasonal norms of roughly 15°C. These conditions favor the tightly matched market leaders at 15°C and 16°C by suppressing solar insolation and promoting mixing of cooler marine air. Minor model differences in the exact timing or intensity of precipitation versus any brief clearing could allow a push toward 17°C or hold readings at 14°C. Updated short-range model runs and official FMI guidance over the next 24–48 hours will provide the clearest signals ahead of market resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHighest temperature in Helsinki on September 18?
Highest temperature in Helsinki on September 18?
16°C 28%
15°C 27%
17°C 13%
14°C 12%
NEW
NEW
Sep 18, 2026
9°C or below
1%
10°C
1%
11°C
1%
12°C
5%
13°C
3%
14°C
12%
15°C
27%
16°C
28%
17°C
13%
18°C
7%
19°C or higher
3%
16°C 28%
15°C 27%
17°C 13%
14°C 12%
NEW
NEW
Sep 18, 2026
9°C or below
$0 Vol.
1%
10°C
$0 Vol.
1%
11°C
$0 Vol.
1%
12°C
$0 Vol.
5%
13°C
$18 Vol.
3%
14°C
$0 Vol.
12%
15°C
$0 Vol.
27%
16°C
$10 Vol.
28%
17°C
$0 Vol.
13%
18°C
$0 Vol.
7%
19°C or higher
$0 Vol.
3%
This market will resolve to the temperature range that contains the highest 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 highest 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.**Forecast models from sources like the Finnish Meteorological Institute, Yr.no, and GFS-based outlooks currently indicate a highest temperature in Helsinki on September 18 most likely between 14–16°C.** Southwesterly flow, persistent cloud cover, and periods of light rain or showers are expected to limit daytime heating, keeping maxima near or slightly above seasonal norms of roughly 15°C. These conditions favor the tightly matched market leaders at 15°C and 16°C by suppressing solar insolation and promoting mixing of cooler marine air. Minor model differences in the exact timing or intensity of precipitation versus any brief clearing could allow a push toward 17°C or hold readings at 14°C. Updated short-range model runs and official FMI guidance over the next 24–48 hours will provide the clearest signals ahead of market resolution.
This market will resolve to the temperature range that contains the highest 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 highest 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 highest 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, 12:58 AM ET
Volume
$27End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:58 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...This market will resolve to the temperature range that contains the highest 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 highest 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.**Forecast models from sources like the Finnish Meteorological Institute, Yr.no, and GFS-based outlooks currently indicate a highest temperature in Helsinki on September 18 most likely between 14–16°C.** Southwesterly flow, persistent cloud cover, and periods of light rain or showers are expected to limit daytime heating, keeping maxima near or slightly above seasonal norms of roughly 15°C. These conditions favor the tightly matched market leaders at 15°C and 16°C by suppressing solar insolation and promoting mixing of cooler marine air. Minor model differences in the exact timing or intensity of precipitation versus any brief clearing could allow a push toward 17°C or hold readings at 14°C. Updated short-range model runs and official FMI guidance over the next 24–48 hours will provide the clearest signals ahead of market resolution.
This market will resolve to the temperature range that contains the highest 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 highest 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 highest 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
$27End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:58 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...**Forecast models from sources like the Finnish Meteorological Institute, Yr.no, and GFS-based outlooks currently indicate a highest temperature in Helsinki on September 18 most likely between 14–16°C.** Southwesterly flow, persistent cloud cover, and periods of light rain or showers are expected to limit daytime heating, keeping maxima near or slightly above seasonal norms of roughly 15°C. These conditions favor the tightly matched market leaders at 15°C and 16°C by suppressing solar insolation and promoting mixing of cooler marine air. Minor model differences in the exact timing or intensity of precipitation versus any brief clearing could allow a push toward 17°C or hold readings at 14°C. Updated short-range model runs and official FMI guidance over the next 24–48 hours will provide the clearest signals ahead of market resolution.
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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