Overview
Helsinki is in Finland. The figures below are long-term monthly averages (2010-2023), not a forecast.
- Warmest month: July, with daytime highs around 21°C.
- Coolest month: January, with daytime highs around -2°C.
- Driest month: March, about 40 mm of rain.
- Wettest month: August, about 86 mm of rain.
- Sunniest month: June, about 14.3 hr of sunshine per day.
Climate by month
| Month | Day high | Night low | Rain (mm) | Rainy days | Sun (h/day) | Humidity | Wind (km/h) |
|---|---|---|---|---|---|---|---|
| January | -2°C | -6°C | 61 mm | 13 | 1.3 | 87% | 17 km/h |
| February | -2°C | -6°C | 53 mm | 11 | 3.3 | 86% | 16 km/h |
| March | 1°C | -4°C | 40 mm | 10 | 7.2 | 82% | 16 km/h |
| April | 7°C | 0°C | 40 mm | 9 | 10.1 | 76% | 14 km/h |
| May | 14°C | 6°C | 55 mm | 10 | 12.6 | 71% | 14 km/h |
| June | 18°C | 12°C | 63 mm | 11 | 14.3 | 71% | 14 km/h |
| July | 21°C | 15°C | 74 mm | 12 | 13.8 | 74% | 13 km/h |
| August | 20°C | 14°C | 86 mm | 13 | 11.3 | 78% | 14 km/h |
| September | 15°C | 10°C | 68 mm | 12 | 8.2 | 82% | 15 km/h |
| October | 9°C | 5°C | 69 mm | 12 | 4.9 | 84% | 17 km/h |
| November | 4°C | 1°C | 68 mm | 13 | 1.9 | 88% | 17 km/h |
| December | 1°C | -3°C | 68 mm | 14 | 1.2 | 87% | 18 km/h |
Similar destinations
Data and sources
- Air climate: Open-Meteo Historical Weather API (ERA5 / ERA5-Land reanalysis), 2010-2023. CC BY 4.0 (Open-Meteo); underlying ERA5 data: Copernicus licence
- Sea temperature: not available for this destination.
- Last updated October 8, 2026.