Forecasts from the Finnish Meteorological Institute and European models project a minimum temperature of 9–11°C in Helsinki on September 28 under high pressure with clear to partly cloudy skies and light southwesterly winds. These conditions favor moderate overnight radiative cooling without strong advection of warmer or colder air masses. Historical September lows average near 8–10°C, providing climatological context, while current model consensus narrows uncertainty around the mid-single digits to low teens Celsius. The near-even market odds between 13°C-or-higher and 3°C-or-below reflect residual spread in ensemble runs and potential for localized variations at the observing station, with traders weighting recent stable high-pressure persistence against any late shifts in steering flow. Updated model guidance expected overnight will likely refine the exact minimum.