Current forecasts from the Finnish Meteorological Institute and ensemble models such as ECMWF project a daytime maximum near 16–17 °C for Helsinki on May 17, driven by southerly flow advecting warmer Atlantic air under partly cloudy skies and light winds. This places the market’s leading 17 °C outcome (39.5 % implied probability) slightly ahead of 16 °C (37.5 %), reflecting modest uncertainty in afternoon boundary-layer mixing and thin high-cloud timing that could cap or briefly exceed the peak. Mid-May climatology at Helsinki-Vantaa station averages 14–15 °C, so these values sit modestly above normal. Traders are watching the final model runs and hourly observations through tomorrow afternoon for any shift in insolation or wind strength that would tip resolution between the two closest brackets.