Weather in Helsinki in August 2025
Average weather
Average temperature in Helsinki in August
The temperature in August is +20°C on average, with a range between a maximum of +28°C during the day and a minimum of +12°C at night.
The average maximum temperature goes up 6% by the end of the month, compared with the beginning of the month, from +18°C to +19°C.
Is Helsinki warm or cold in August?
Helsinki is typically mild in August.
Maximum temperatures go down compared to the previous month from +20°C to +19°C. The minimum temperature also goes down from +14°C to +13°C.
Pack a light jacket as it will be warm in the day and cool in the evenings.
August is one of the warmest months in Helsinki, here is the comparison with other months:
Water temperature in Helsinki in August
Water in Helsinki in August is Cold. It varies from +3°C to +23°C, with an average of +13°C. The air temperature averaging +19°C is higher than the water temperature.
The water temperature in August is one of the warmest of the entire year:
Can you swim in Helsinki in August?
Climate in Helsinki in August
| July | August | September | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +20°C | +19°C | +14°C | ||||
| Min. temperature | ||||||
| +7°C | +3°C | 0°C | ||||
| Max. temperature | ||||||
| +32°C | +29°C | +22°C | ||||
| Rainfall | ||||||
| 69 mm | 83 mm | 78 mm | ||||
| Wind | ||||||
| 3 m/s | 3 m/s | 4 m/s | ||||
| Avg. water temperature | ||||||
| +12°C | +13°C | +10°C | ||||
| Humidity | ||||||
| 72% | 76% | 81% | ||||
| Air pressure | ||||||
| 1010 HPa | 1011 HPa | 1011 HPa | ||||
| Sunny days | ||||||
| 10 | 8 | 5 | ||||
| Cloudy days | ||||||
| 5 | 5 | 8 | ||||
| Rainy days | ||||||
| 12 | 15 | 16 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
August typically has worse weather conditions compared to July. It’s getting colder in August. From +20°C in the day, the average maximum temperature lowers to +19°C. Prepare for more rain. Average rainfall goes from 69 mm to 83 mm. Humidity rises from 72% to 76%. The average wind speed doesn’t change much during August, staying around 3 m/s. The days becoming less sunny, going from 10 sunny days in July to 8 in August.
September brings much the same weather, it remains ok.
Wind
The average wind speed is 5 m/s getting up to 11 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in Helsinki is gradually increasing during August, going from 5 m/s to 7 m/s over the course of the month.
Rain
How was the weather last August in Helsinki?
Climate Change over Years
The climate in Helsinki in August has not changed much over the last 43 years.
The average temperature was the lowest in 1987 (+5°C) and the highest in 2020 (+11°C). The driest year was 2002 with only 248 mm of rainfall, and the wettest year was 2020 with 1153 mm.
FAQ
Is August a good time to visit Helsinki?
Can you sunbathe in Helsinki in August?
Can you swim in Helsinki in August?
Is Helsinki rainy in August?
Is it sunny in Helsinki in August?
Other cities in Finland
Monthly weather in Helsinki
Source of the data
For this page, we’ve looked at the typical weather in Helsinki, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.