Forecast models from the Finnish Meteorological Institute indicate a daytime high near 19°C for Helsinki on August 20, consistent with the late-summer cooling trend and Baltic Sea moderation that typically caps maxima in the high teens to low twenties. Ensemble guidance shows limited spread, with most runs clustering between 18–21°C under generally zonal flow and modest insolation. Historical August averages near 20°C provide context, but the observed progression from mid-month peaks supports the current market emphasis on 19°C as the mode. Short-term revisions remain possible with updated runs, particularly if cloud cover or wind shifts alter the diurnal range.