Sun, sea & sand

Vaasa weather in September

Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.

18

Holiday weather in September

Poor

Best time to visit: May, July

What is the weather like in Vaasa in September?

In September, Vaasa is cool: daytime highs average 14 °C, and nights cool down to about 9 °C. The sea averages 13.2 °C – swimming is only for the hardy. Expect around 5 hours of sunshine a day. Rain is frequent, with about 10 rainy days and 53 mm in total. All in all, September is not an ideal month for a holiday in Vaasa.

September compared

How the weather changes from August to October. Tap a month to open it.

AugustAugSeptemberSepOctoberOct
Score221811
Day19°14°7°
Night13°9°4°
Sea16°13°9°
Sun7 h5 h3 h
Rain days121011

More details for September

Daylight
13 h 8 min06:55 – 20:03
UV index
2 · lowclear sky, noon (estimate)All months
Muggy days
0 daysdew point 18 °C or moreAll months
Wind
19 km/haverage daily peakAll months
Cloud cover
66 %on averageAll months
Hot days
0 days30 °C or more
Snow days
0 days1 cm or more of fresh snowAll months
Time zone
UTC+3Europe/Helsinki

How the score comes together

  • Temperatureweight 35 %0 %
  • Seaweight 25 %0 %
  • Sunshineweight 20 %35 %
  • Few rainy daysweight 20 %56 %

Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.

What to pack in September

  • A jumper for the evenings
  • Rain jacket or umbrella

Vaasa in September: quick answers

Is Vaasa hot in September?

No. In September, Vaasa is cool: daytime highs average 14 °C and nights drop to about 9 °C.

Can you swim in Vaasa in September?

Only if you don't mind cold water: in September the sea averages just 13.2 °C. Comfortable swimming temperatures are not reached at any time of year.

Does it rain much in Vaasa in September?

Rain is frequent, with about 10 rainy days and 53 mm in total.

Vaasa month by month

Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences