Recent ensemble forecasts from models such as ECMWF and GFS indicate a highest temperature of 15–16 °C for Helsinki on September 21, driven by a shift to northerly flow behind a weakening frontal system that brings cooler maritime air and scattered showers. Daytime maxima are expected to peak in the afternoon under partly cloudy skies with light winds around 4–6 m/s, limiting warming compared to the preceding southwesterly regime. This aligns closely with late-September climatology near 14–15 °C while reflecting modest above-normal conditions from recent model runs. Market-implied odds favor 16 °C as the modal outcome, with uncertainty mainly in exact cloud cover and precipitation timing that could trim or add 1 °C. Updated short-range guidance through the weekend will refine these probabilities ahead of 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 21?
Highest temperature in Helsinki on September 21?
16°C 45%
17°C 28%
15°C 25%
18°C 7%
NEW
NEW
Sep 21, 2026
10°C or below
<1%
11°C
1%
12°C
2%
13°C
6%
14°C
6%
15°C
20%
16°C
45%
17°C
28%
18°C
7%
19°C
2%
20°C or higher
1%
16°C 45%
17°C 28%
15°C 25%
18°C 7%
NEW
NEW
Sep 21, 2026
10°C or below
$197 Vol.
<1%
11°C
$91 Vol.
1%
12°C
$0 Vol.
2%
13°C
$31 Vol.
6%
14°C
$0 Vol.
6%
15°C
$24 Vol.
20%
16°C
$777 Vol.
45%
17°C
$171 Vol.
28%
18°C
$85 Vol.
7%
19°C
$62 Vol.
2%
20°C or higher
$166 Vol.
1%
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 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=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 ensemble forecasts from models such as ECMWF and GFS indicate a highest temperature of 15–16 °C for Helsinki on September 21, driven by a shift to northerly flow behind a weakening frontal system that brings cooler maritime air and scattered showers. Daytime maxima are expected to peak in the afternoon under partly cloudy skies with light winds around 4–6 m/s, limiting warming compared to the preceding southwesterly regime. This aligns closely with late-September climatology near 14–15 °C while reflecting modest above-normal conditions from recent model runs. Market-implied odds favor 16 °C as the modal outcome, with uncertainty mainly in exact cloud cover and precipitation timing that could trim or add 1 °C. Updated short-range guidance through the weekend will refine these probabilities ahead of 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 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=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 19, 2026, 12:58 AM ET
Volume
$1,552End Date
Sep 21, 2026Market Opened
Sep 19, 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 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=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 ensemble forecasts from models such as ECMWF and GFS indicate a highest temperature of 15–16 °C for Helsinki on September 21, driven by a shift to northerly flow behind a weakening frontal system that brings cooler maritime air and scattered showers. Daytime maxima are expected to peak in the afternoon under partly cloudy skies with light winds around 4–6 m/s, limiting warming compared to the preceding southwesterly regime. This aligns closely with late-September climatology near 14–15 °C while reflecting modest above-normal conditions from recent model runs. Market-implied odds favor 16 °C as the modal outcome, with uncertainty mainly in exact cloud cover and precipitation timing that could trim or add 1 °C. Updated short-range guidance through the weekend will refine these probabilities ahead of 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 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=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
$1,552End Date
Sep 21, 2026Market Opened
Sep 19, 2026, 12:58 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...Recent ensemble forecasts from models such as ECMWF and GFS indicate a highest temperature of 15–16 °C for Helsinki on September 21, driven by a shift to northerly flow behind a weakening frontal system that brings cooler maritime air and scattered showers. Daytime maxima are expected to peak in the afternoon under partly cloudy skies with light winds around 4–6 m/s, limiting warming compared to the preceding southwesterly regime. This aligns closely with late-September climatology near 14–15 °C while reflecting modest above-normal conditions from recent model runs. Market-implied odds favor 16 °C as the modal outcome, with uncertainty mainly in exact cloud cover and precipitation timing that could trim or add 1 °C. Updated short-range guidance through the weekend will refine these probabilities ahead of 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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