Current forecasts from sources like the Finnish Meteorological Institute and Yr.no indicate overnight lows near 11–13°C for Helsinki on September 18, with daytime highs around 14–16°C amid southerly flow, widespread cloud cover, and periods of rain tied to a low-pressure system. Trader consensus clustering on 7–10°C minimums reflects model spread in nocturnal radiative cooling, where thicker clouds and precipitation limit temperature drops while lighter winds allow greater surface cooling toward the lower end of outcomes. Historical September averages near 9°C provide context, but this event’s mild advection and unsettled pattern reduce the chance of extremes below 6°C or above 12°C. Updated model runs and official briefings over the next 48 hours will refine the minimum threshold.
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?
10°C 40%
7°C 38%
8°C 38%
9°C 38%
NEW
NEW
Sep 18, 2026
5°C or below
9%
6°C
19%
7°C
38%
8°C
38%
9°C
38%
10°C
40%
11°C
19%
12°C
11%
13°C
7%
14°C
5%
15°C or higher
5%
10°C 40%
7°C 38%
8°C 38%
9°C 38%
NEW
NEW
Sep 18, 2026
5°C or below
$0 Vol.
9%
6°C
$0 Vol.
19%
7°C
$0 Vol.
38%
8°C
$0 Vol.
38%
9°C
$0 Vol.
38%
10°C
$0 Vol.
40%
11°C
$0 Vol.
19%
12°C
$0 Vol.
11%
13°C
$0 Vol.
7%
14°C
$0 Vol.
5%
15°C or higher
$0 Vol.
5%
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.Current forecasts from sources like the Finnish Meteorological Institute and Yr.no indicate overnight lows near 11–13°C for Helsinki on September 18, with daytime highs around 14–16°C amid southerly flow, widespread cloud cover, and periods of rain tied to a low-pressure system. Trader consensus clustering on 7–10°C minimums reflects model spread in nocturnal radiative cooling, where thicker clouds and precipitation limit temperature drops while lighter winds allow greater surface cooling toward the lower end of outcomes. Historical September averages near 9°C provide context, but this event’s mild advection and unsettled pattern reduce the chance of extremes below 6°C or above 12°C. Updated model runs and official briefings over the next 48 hours will refine the minimum threshold.
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
$0End 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.Current forecasts from sources like the Finnish Meteorological Institute and Yr.no indicate overnight lows near 11–13°C for Helsinki on September 18, with daytime highs around 14–16°C amid southerly flow, widespread cloud cover, and periods of rain tied to a low-pressure system. Trader consensus clustering on 7–10°C minimums reflects model spread in nocturnal radiative cooling, where thicker clouds and precipitation limit temperature drops while lighter winds allow greater surface cooling toward the lower end of outcomes. Historical September averages near 9°C provide context, but this event’s mild advection and unsettled pattern reduce the chance of extremes below 6°C or above 12°C. Updated model runs and official briefings over the next 48 hours will refine the minimum threshold.
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
$0End Date
Sep 18, 2026Market Opened
Sep 16, 2026, 12:31 AM ETResolution Source
https://www.weather.gov/wrh/timeseries?site=efhkResolver
0x69c47De9D...Current forecasts from sources like the Finnish Meteorological Institute and Yr.no indicate overnight lows near 11–13°C for Helsinki on September 18, with daytime highs around 14–16°C amid southerly flow, widespread cloud cover, and periods of rain tied to a low-pressure system. Trader consensus clustering on 7–10°C minimums reflects model spread in nocturnal radiative cooling, where thicker clouds and precipitation limit temperature drops while lighter winds allow greater surface cooling toward the lower end of outcomes. Historical September averages near 9°C provide context, but this event’s mild advection and unsettled pattern reduce the chance of extremes below 6°C or above 12°C. Updated model runs and official briefings over the next 48 hours will refine the minimum threshold.
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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