Mariehamn Weather in December
During December, Mariehamn experiences low daytime temperatures of 5°C (41°F) and cooler nights around 1°C (34°F). Expect quite a bit of rainfall. Around 62 mm (2.4 in) is typical.
Rainfall in Mariehamn in December
You can expect rain on around 19 days based on historical patterns, with 62 mm (2.4 in) average for the month. This is a month with many wet days but modest rainfall totals, so showers are generally light and easy to manage.
Temperature in Mariehamn in December
In December, Mariehamn gets low temperatures, with highs of 5°C (41°F). Nights cool to around 1°C (34°F). Even daytime conditions remain cold, making layers, a warm coat, and winter accessories a good idea. With overnight lows of 1°C (34°F), nights are cold. The cold air does make for deep, comfortable sleep if you have enough blankets. Expect freezing temperatures this month, so ensure you have plenty of warm clothing. It's important to be prepared.December in Mariehamn can still be great, but if you prefer pleasant temperatures along with dry and sunny conditions, our weather planner can help you explore other options in the world.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Finland, check out our Mariehamn's climate page.
Mariehamn Temperature in December
Min Temperature
1°C (34°F)
Max Temperature
5°C (41°F)
Chance of Rain
62%
Precipitation
62 mm (2.4 in)
Rainy days
19 days
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Mariehamn typically stay consistent throughout December, with daily highs averaging around 5°C (41°F). Nights are very cold, with lows typically ranging from -4°C (25°F) to -1°C (30°F).
Average temperatures in December
Historical weather for Mariehamn in December
Browse day-by-day weather records for Mariehamn spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Mariehamn historical weather extremes in December
The extremes listed below come from historical weather data collected in Mariehamn from 1976 through 2025.
- On December 5, 2015, temperatures climbed to 11°C (52°F), marking the warmest December day on record.
Best Places in Finland in December
Find out more about the weather in Finland and which places have the best travel conditions in this month. See all of Finland in December →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Mariehamn in December
Cold weather calls for smart layering in December. A thermal base layer makes a huge difference in staying warm. Add a wool sweater or fleece, then a wind-resistant outer jacket. Rain gear is recommended, you can expect wet weather on multiple days.What To Do in Mariehamn in December
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Finland, check out our Mariehamn's climate page.
See the full Mariehamn climate overview or explore weather in Finland.
