Ensemble forecasts from the Finnish Meteorological Institute and ECMWF currently project a daytime maximum near 19°C for Helsinki on May 16, driven by mild southerly advection of warmer Atlantic air beneath a high-pressure ridge combined with moderate solar heating under partly cloudy skies. This positions the 19°C outcome at near-certain market-implied odds, consistent with observed morning temperatures around 13–14°C and climatological May averages of 14–16°C. Subtle uncertainties remain in boundary-layer mixing and the exact timing of any high cloud build-up that could limit peak insolation. New hourly FMI observations through the afternoon and any late model runs could shift the final reading by 1–2°C, though significant deviations appear unlikely given the stable synoptic pattern.