See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
13°
Overcast
Feels Like: 13°
Min: 12°
Max: 15°
The next few hours will be overcast, with today reaching 15°C and dropping to 12°C. The coming days will be breezy
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
07:43
Sunrise
19:18
Sunset
Moon
Waxing Gibbous
18:59
Moonrise
05:36
Moonset
Daily Forecast
Today
Saturday
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
Air Quality Data Available
Upgrade to access real-time air quality data for Mariehamn.
UV Index
Humidity
Current stargazing conditions?
See sky darkness, moon phase, and the best viewing window for Mariehamn.
View stargazing scoreWeather in Mariehamn today, September 25, 2026
Mariehamn starts September 25, 2026 looking damp, with rain in the forecast and wetter spells likely at times. Waterproof kit is the safer call for early plans. The morning carries the wetter risk, with rain chances near 94% and the highest odds around 10:00. Cloud is also thick early on, peaking near 100% around 07:00.
The temperature range runs from about 12°C up to 15°C. The air stays humid, with relative humidity between 79% and 96% and the peak around 22:00. Airflow remains manageable, reaching about 6.1 km/h around 07:00.
Through the afternoon wet weather remains a factor, with rain chances near 34% around 17:00. Cloud also stays substantial, close to 99% near 19:00. Horizontal visibility sits around 21.0 km, briefly nearer 6.8 km. Sunrise is at 07:43 and sunset at 19:18, giving 11 hours 34 minutes of sunlight today.
Overall, Mariehamn on September 25, 2026 suits indoor plans or waterproof kit, especially while rain chances stay near 94% and the high sits around 15°C.
Frequently asked questions about weather in Mariehamn
How warm does it get in Mariehamn?
The warmest month in Mariehamn is July, with average high temperatures of 18°C. The average temperature during this period is around 17°C.
How cold does it get in Mariehamn?
The coldest month in Mariehamn is February, with average low temperatures of -1°C. The average temperature during this period is around 0°C.
What is the wettest time of year in Mariehamn?
The wettest month in Mariehamn is October, with an average of 78mm of precipitation.
What is the driest time of year in Mariehamn?
The driest month in Mariehamn is April, with an average of 28mm of precipitation.
