Mariehamn — Water Temperature in October
Water Temperature Range
0°C
minimum
9°C
average
15°C
maximum
Water Temperature Chart for Month
The chart shows the average daily water temperature for each day of the month based on historical data.
Table of Water Temperatures by Day of the Month for Previous Years
| Day | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| OCT 1 | 13°C | 14°C | 12°C | 13°C |
| OCT 2 | 12°C | 13°C | 12°C | 13°C |
| OCT 3 | 12°C | 14°C | 12°C | 13°C |
| OCT 4 | 12°C | 13°C | 12°C | 13°C |
| OCT 5 | 12°C | 12°C | 12°C | 13°C |
| OCT 6 | 12°C | 12°C | 11°C | 13°C |
| OCT 7 | 11°C | 12°C | 11°C | 13°C |
| OCT 8 | 11°C | 12°C | 12°C | 12°C |
| OCT 9 | 11°C | 11°C | 12°C | 12°C |
| OCT 10 | 11°C | 12°C | 12°C | 12°C |
| OCT 11 | 11°C | 12°C | 12°C | 12°C |
| OCT 12 | 11°C | 12°C | 11°C | 12°C |
| OCT 13 | 11°C | 12°C | 11°C | 12°C |
| OCT 14 | 11°C | 12°C | 12°C | 12°C |
| OCT 15 | 10°C | 11°C | 12°C | 11°C |
| OCT 16 | 10°C | 11°C | 12°C | 11°C |
| OCT 17 | 8°C | 11°C | 11°C | 11°C |
| OCT 18 | 8°C | 11°C | 10°C | 11°C |
| OCT 19 | 8°C | 10°C | 10°C | 11°C |
| OCT 20 | 8°C | 11°C | 10°C | 10°C |
| OCT 21 | 7°C | 10°C | 9°C | 10°C |
| OCT 22 | 7°C | 9°C | 10°C | 10°C |
| OCT 23 | 7°C | 9°C | 9°C | 10°C |
| OCT 24 | 7°C | 9°C | 9°C | 10°C |
| OCT 25 | 7°C | 9°C | 9°C | 10°C |
| OCT 26 | 7°C | 9°C | 9°C | 10°C |
| OCT 27 | 7°C | 9°C | 9°C | 9°C |
| OCT 28 | 7°C | 9°C | 9°C | 9°C |
| OCT 29 | 7°C | 10°C | 9°C | 9°C |
| OCT 30 | 7°C | 9°C | 9°C | 10°C |
| OCT 31 | 7°C | 9°C | 9°C | 9°C |
October: Climate and Swimming Opportunities
Average Night Air Temperature
3°C
Average Day Air Temperature
7°C
Precipitation Amount per Month
74 mm
Number of Rainy Days
12
Daylight per Day
10 hrs
Sunshine per Day
3 hrs
Average Wind Speed
18 km/h
Average Humidity
86%
At such water and air temperatures, swimming is extremely harsh and generally not enjoyable. The risk of rapid chilling is high, so most people avoid entering the water.