Recent short-range forecast models from the Finnish Meteorological Institute point to a daily high near 19–21 °C in Helsinki on May 18, driven by moderate southwesterly flow, partial cloud cover, and limited daytime heating over the Baltic. Springtime temperature variability remains high at this latitude because small shifts in cloud thickness or wind direction can easily move the peak by 2–3 °C. Historical May maxima average 15–16 °C, yet recent years show occasional excursions above 20 °C when high-pressure ridges strengthen; traders therefore assign the largest share of probability to the narrow 19–21 °C band while leaving room for either a cooler maritime air mass or brief clearing that could push readings higher. Updated model runs expected overnight will clarify whether the current consensus holds.