Finland
Turku in September: weather, sea & travel advice
This month's data profile
Clear transition month
Turku in September is climatically well suited to city breaks. The average daily high is around 16 °C, and the sea is about 14 °C. With about 11 rainy days it is wet.
Historical monthly averages, not a weather forecast. Individual days and years can differ substantially.
Rank among 12 monthly averages
44/100 · #5
Warmth
#4
Dryness
#4
Sun
#6
Sea warmth
#3
Published best categories: none
Turku · SeptemberPhoto: Kotivalo · CC0Climate facts
- Average high
- 16 °C
- Average low
- 8 °C
- Sea
- 14 °C
- Rainy days (est.)
- 11 rainy days (est.)
- Sun (est.)
- 3 h/day
- Humidity
- 84 %
Climate evidence with direct month comparison
The highlighted row is the selected month. Precipitation total and rainy days are separate monthly averages.
| Month | Avg high °C | Avg low °C | Rainy days (est.) | Precipitation mm | Sun h/day (est.) | Humidity % | Wind m/s | Sea °C | Score |
|---|---|---|---|---|---|---|---|---|---|
| August | 21 | 12 | 13 | 75 | 5.1 | 79 | 0.6 | 17 | 61 |
| September (selected) | 16 | 8 | 11 | 61 | 3.1 | 84 | 0.6 | 14 | 44 |
| October | 9 | 3 | 13 | 81 | 1.3 | 91 | 0.6 | 10 | 22 |
How do the previous and next months compare?
Baseline: September (44/100)
Positive and negative values show the change from the selected month.
| Score Δ | Average high Δ | Average low Δ | Rainy days Δ | Rain Δ | Sun Δ | Humidity Δ | Wind Δ | Sea Δ | |
|---|---|---|---|---|---|---|---|---|---|
| August | +17 | +5 °C | +4 °C | +2.1 | +14.3 mm | +2 h | -4.9 % | -0.1 m/s | +2.9 °C |
| October | -22 | -7 °C | -4.8 °C | +2.7 | +20.6 mm | -1.8 h | +6.4 % | ±0 m/s | -3.9 °C |
All twelve months in context
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Where to stay in Turku
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Useful next decisions
Frequently asked questions
How warm is Turku in September?
The average daily high is around 16 °C, with an average daily low of about 8 °C.
Can you swim in Turku in September?
The sea is about 14 °C (cold).
Does it rain a lot in Turku in September?
The curated estimate is about 11 rainy days per month, not a directly measured long-term average. Total precipitation averages around 61 mm for the month. A rainy day does not mean all-day rain.
When is the best time to visit Turku?
By the climate score, July and August are the strongest months for Turku. September is not among them.