Persistent rain and southerly flow are expected to limit daytime warming in Helsinki on September 26, with official and ensemble forecasts from the Finnish Meteorological Institute and other models converging on a daily high of 14–15 °C amid widespread showers and cloud cover. This range aligns closely with the late-September climatological average high of roughly 13.4 °C while the added moisture and limited insolation reduce the chance of exceeding 15 °C. Market-implied odds reflect this tight consensus, with only modest probability assigned to 13 °C or 16 °C outcomes that would require notable model shifts in steering or precipitation timing. Updated guidance later today or tomorrow morning will determine whether any brief clearing allows a marginal push toward the upper end of the favored band.