Recent numerical weather prediction runs from models such as GFS indicate a mild, cloudy pattern over southern Finland on September 25, with daytime maxima most likely reaching 13–14 °C under persistent northerly flow and scattered showers. These conditions limit solar heating while preventing sharp cooling, aligning with the climatological September average high near 13 °C at Helsinki-Vantaa. Ensemble spread remains narrow because the synoptic setup shows little variation in timing or intensity of the precipitation shield, producing closely matched market-implied probabilities for 12–14 °C. Traders appear to weigh the modest upside risk from brief clearing against the higher likelihood of rain-cooled afternoons, keeping the 13 °C and 14 °C contracts dominant ahead of the final observational window.