Last updated: August 23, 2025
In Ilmajoki, Finland, the average temperature in September hovers around 10°C (50°F), with a minimum dipping to -3°C (27°F) and a maximum soaring to 24°C (75°F). Expect 73 mm (2.9 in) of precipitation over about 13 days, contributing to a relatively high average humidity of 88%.
In September in Ilmajoki, the average temperature is 10°C (50°F), with maximums reaching 24°C (75°F) and minimums plummeting to as low as -3°C (27°F). Be prepared for a mix of mild days and chilly nights when traveling during this time.
In Ilmajoki in September, the precipitation amount is 73 mm (2.9 in) over the course of 13 days.
In Ilmajoki in September, humidity is 88%. With an average temperature of 10°C (50°F), this humidity feels like a damp chill that seeps into your bones, making outdoor exploration uncomfortable and encouraging travelers to seek cozy indoor activities instead.
In Ilmajoki in September, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Ilmajoki, you can check the information here.
UV Risk Categories
Weather in Ilmajoki varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Ilmajoki, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -4°C (25°F) | 36 mm (1.4 inches) | 95% | low |
| February Weather | -5°C (23°F) | 38 mm (1.5 inches) | 93% | low |
| March Weather | -2°C (29°F) | 41 mm (1.6 inches) | 91% | moderate |
| April Weather | 3°C (38°F) | 42 mm (1.7 inches) | 85% | moderate |
| May Weather | 9°C (49°F) | 56 mm (2.2 inches) | 77% | moderate |
| June Weather | 15°C (60°F) | 61 mm (2.4 inches) | 74% | high |
| July Weather | 17°C (63°F) | 57 mm (2.2 inches) | 80% | high |
| August Weather | 15°C (59°F) | 90 mm (3.5 inches) | 82% | moderate |
| September Weather | 10°C (50°F) | 73 mm (2.9 inches) | 88% | moderate |
| October Weather | 5°C (41°F) | 73 mm (2.9 inches) | 92% | low |
| November Weather | 1°C (34°F) | 57 mm (2.2 inches) | 92% | low |
| December Weather | -2°C (28°F) | 47 mm (1.8 inches) | 93% | low |