Last updated: August 23, 2025
In Koski Tl, Finland, the average temperature in December hovers around -2°C (30°F). However, temperatures can fluctuate significantly, dipping to a chilling -20°C (-3°F) at their lowest and peaking at 6°C (43°F). Expect 67 mm (2.6 in) of precipitation over approximately 13 days, while humidity remains high at 95%.
In December in Koski Tl, the average temperature is -2°C (30°F), with maximums reaching 6°C (43°F) and minimums dropping as low as -20°C (-3°F). Be sure to pack warm clothing if you're planning to visit during this chilly time of year!
In Koski Tl in December, the precipitation amount is 67 mm (2.6 in) spread over 13 days.
In Koski Tl in December, humidity is 95%. With an average temperature of -2°C (30°F), this humidity feels like an icy blanket wrapping around you, making even short walks feel biting and uncomfortable, perfect for those who enjoy the chill but challenging for travelers seeking comfort.
In Koski Tl 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 Koski Tl.
UV Risk Categories
Weather in Koski Tl varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Koski Tl, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -3°C (27°F) | 49 mm (1.9 inches) | 97% | low |
| February Weather | -4°C (25°F) | 44 mm (1.7 inches) | 95% | low |
| March Weather | -1°C (30°F) | 46 mm (1.8 inches) | 93% | moderate |
| April Weather | 4°C (39°F) | 41 mm (1.6 inches) | 86% | moderate |
| May Weather | 10°C (50°F) | 59 mm (2.3 inches) | 75% | moderate |
| June Weather | 16°C (62°F) | 59 mm (2.3 inches) | 75% | high |
| July Weather | 17°C (64°F) | 83 mm (3.3 inches) | 80% | high |
| August Weather | 16°C (61°F) | 88 mm (3.5 inches) | 83% | moderate |
| September Weather | 11°C (52°F) | 62 mm (2.4 inches) | 90% | moderate |
| October Weather | 6°C (43°F) | 77 mm (3.0 inches) | 93% | low |
| November Weather | 2°C (37°F) | 52 mm (2.1 inches) | 94% | low |
| December Weather | -2°C (30°F) | 67 mm (2.6 inches) | 95% | low |