The highest day temperature in August 2025 was 75°F. The lowest night temperature was 47°F. The average values for day and night temperatures during August were 66.5°F и 56.5°F respectivly.

The average sea surface temperature in August 2025 for Helsinki was 65.3°F. The maximum and minimum values were 57.2°F and 76.6°F respectively.

Most of the days in August are sunny but you can also expect cloudy and gloomy days.

Precipitation total in August for Helsinki is 2.2 in. It makes august one of the most rainy months of the year.

The average wind speed in August is 9.5 mph. It makes August one of the most windless months of the year for Helsinki.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Helsinki in August is 9.4 hours.