**Latest ensemble forecasts from European and global models show Helsinki's June 15 maximum temperature most likely falling between 16–18°C, aligning with the tight market clustering around those outcomes.** Variations stem primarily from differences in predicted cloud cover, timing of any weak fronts, and boundary-layer mixing under light southerly flow. The Baltic Sea's cool surface waters provide a strong moderating influence, limiting daytime warming despite long June daylight hours, while modest solar heating under partly cloudy skies could push readings toward 18°C if clearer conditions prevail in the afternoon. Official guidance from the Finnish Meteorological Institute and international centers highlights this narrow range, with ensemble spreads reflecting typical uncertainty this close to the event. Traders are weighting the most recent model runs heavily, as small shifts in predicted insolation or advection can easily move the daily high by 1–2°C.