**Divergent ensemble model outputs and uncertain overnight radiative cooling under variable cloud cover and northerly flow are the main drivers keeping trader-implied probabilities closely matched between sub-3 °C and 12 °C+ outcomes for Helsinki’s September 23 minimum.** Baltic Sea moderation typically limits sharp drops, yet forecasts from ECMWF, GFS, and regional runs show spread in low-level advection and precipitation timing that could either enhance or suppress surface cooling. Historical September climatology places average overnight lows near 8 °C, but any shift in frontal timing or wind strength before official station measurement can alter the realized minimum by several degrees, sustaining the broad distribution of market-implied odds.
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 23?
Lowest temperature in Helsinki on September 23?
2°C or below 63%
12°C or higher 63%
10°C 39%
4°C 38%
NEW
NEW
Sep 23, 2026
2°C or below
63%
3°C
11%
4°C
38%
5°C
25%
6°C
28%
7°C
23%
8°C
21%
9°C
19%
10°C
39%
11°C
1%
12°C or higher
63%
2°C or below 63%
12°C or higher 63%
10°C 39%
4°C 38%
NEW
NEW
Sep 23, 2026
2°C or below
$100 Vol.
63%
3°C
$40 Vol.
11%
4°C
$8 Vol.
38%
5°C
$0 Vol.
25%
6°C
$0 Vol.
28%
7°C
$0 Vol.
23%
8°C
$0 Vol.
21%
9°C
$0 Vol.
19%
10°C
$25 Vol.
39%
11°C
$100 Vol.
1%
12°C or higher
$200 Vol.
63%
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 23 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.**Divergent ensemble model outputs and uncertain overnight radiative cooling under variable cloud cover and northerly flow are the main drivers keeping trader-implied probabilities closely matched between sub-3 °C and 12 °C+ outcomes for Helsinki’s September 23 minimum.**
Baltic Sea moderation typically limits sharp drops, yet forecasts from ECMWF, GFS, and regional runs show spread in low-level advection and precipitation timing that could either enhance or suppress surface cooling. Historical September climatology places average overnight lows near 8 °C, but any shift in frontal timing or wind strength before official station measurement can alter the realized minimum by several degrees, sustaining the broad distribution of market-implied odds.
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 23 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 21, 2026, 12:31 AM ET
Volume
$474End Date
Sep 23, 2026Market Opened
Sep 21, 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 23 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.**Divergent ensemble model outputs and uncertain overnight radiative cooling under variable cloud cover and northerly flow are the main drivers keeping trader-implied probabilities closely matched between sub-3 °C and 12 °C+ outcomes for Helsinki’s September 23 minimum.**
Baltic Sea moderation typically limits sharp drops, yet forecasts from ECMWF, GFS, and regional runs show spread in low-level advection and precipitation timing that could either enhance or suppress surface cooling. Historical September climatology places average overnight lows near 8 °C, but any shift in frontal timing or wind strength before official station measurement can alter the realized minimum by several degrees, sustaining the broad distribution of market-implied odds.
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 23 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
$474End Date
Sep 23, 2026Market Opened
Sep 21, 2026, 12:31 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...**Divergent ensemble model outputs and uncertain overnight radiative cooling under variable cloud cover and northerly flow are the main drivers keeping trader-implied probabilities closely matched between sub-3 °C and 12 °C+ outcomes for Helsinki’s September 23 minimum.** Baltic Sea moderation typically limits sharp drops, yet forecasts from ECMWF, GFS, and regional runs show spread in low-level advection and precipitation timing that could either enhance or suppress surface cooling. Historical September climatology places average overnight lows near 8 °C, but any shift in frontal timing or wind strength before official station measurement can alter the realized minimum by several degrees, sustaining the broad distribution of market-implied odds.
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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