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 9 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 forecast consensus from the Finnish Meteorological Institute and international models indicates a highest temperature in Helsinki on September 9 most likely near 17–18 °C, driven by mild southwesterly flow and partly cloudy skies with scattered showers. This aligns with the seasonal decline from summer peaks yet sits above the 1991–2020 daily average high of 16.6 °C for the date. Recent developments include a warming trend across southern Finland after cooler nights, with ensemble guidance showing limited model spread around these values and low probability of exceeding 19 °C or falling below 16 °C. Traders appear to weight the latest model runs and historical climatology heavily, producing tight clustering on the two leading outcomes.