Last updated: August 23, 2025
In December, the average temperature in Ilomantsi, Finland hovers around -5°C (24°F), with lows plummeting to a frigid -26°C (-15°F) and occasionally reaching a maximum of 3°C (38°F). Expect 71 mm (2.8 in) of precipitation spread over 16 days, and brace yourself for a high average humidity of 97%, making it a chilly and damp month!
In December in Ilomantsi, the average temperature is -5°C (24°F). The maximum can reach 3°C (38°F), while the minimum can be as low as -26°C (-15°F). Travelers should be prepared for extremely cold conditions and dress warmly when visiting during this time.
In Ilomantsi in December, the precipitation amount is 71 mm (2.8 in) over the course of 16 days.
In Ilomantsi in December, humidity is 97%. With an average temperature of -5°C (24°F), this humidity feels like a bone-chilling mist that clings to your skin, making every breath a reminder of the frigid air, and turning your travel into an exhilarating but challenging adventure through a frosty landscape.
In Ilomantsi in December, the maximum UV index is 1, which corresponds to a low Exposure Category. This means you have a time to burn of 45 minutes. For more details, you can check the Hourly UV Index in Ilomantsi.
UV Risk Categories
Weather in Ilomantsi varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Ilomantsi, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -8°C (19°F) | 49 mm (1.9 inches) | 99% | low |
| February Weather | -8°C (18°F) | 50 mm (2.0 inches) | 98% | low |
| March Weather | -4°C (25°F) | 54 mm (2.1 inches) | 95% | moderate |
| April Weather | 1°C (35°F) | 46 mm (1.8 inches) | 88% | moderate |
| May Weather | 9°C (48°F) | 60 mm (2.4 inches) | 79% | moderate |
| June Weather | 15°C (60°F) | 60 mm (2.3 inches) | 76% | high |
| July Weather | 17°C (62°F) | 95 mm (3.7 inches) | 83% | high |
| August Weather | 15°C (59°F) | 105 mm (4.1 inches) | 89% | moderate |
| September Weather | 9°C (49°F) | 78 mm (3.1 inches) | 91% | moderate |
| October Weather | 4°C (40°F) | 85 mm (3.4 inches) | 95% | low |
| November Weather | 0°C (31°F) | 61 mm (2.4 inches) | 95% | low |
| December Weather | -5°C (24°F) | 71 mm (2.8 inches) | 97% | low |