Last updated: August 22, 2025
In Kalmthout, Belgium, the average temperature in September is a mild 15°C (60°F). However, be prepared for a range; temperatures can drop to a chilly 3°C (38°F), soaring up to a warm 32°C (90°F). During this month, expect about 61 mm (2.4 in) of precipitation spread over 10 days, contributing to an average humidity of 82%. Enjoy the diverse climate, but don’t forget your umbrella!
In September in Kalmthout, the average temperature is 15°C (60°F). Maximums can reach 32°C (90°F), while minimums can drop as low as 3°C (38°F). This variation in temperature makes it essential to pack both light clothing for warmth and a jacket for cooler evenings when traveling.
In Kalmthout in September, the precipitation amount is 61 mm (2.4 in) over a span of 10 days.
In Kalmthout in September humidity is 82%. With an average temperature of 15°C (60°F), this humidity feels like a heavy blanket wrapping around you, making outdoor activities feel sticky and draining, which can hinder your travel experience.
In Kalmthout in September, the maximum UV index reaches 5, which corresponds to a moderate Exposure Category. Under these conditions, the estimated time to burn is approximately 30 minutes. For more details, you can check the Hourly UV Index in Kalmthout.
UV Risk Categories
Weather in Kalmthout varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Kalmthout, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 4°C (40°F) | 63 mm (2.5 inches) | 91% | low |
| February Weather | 5°C (42°F) | 66 mm (2.6 inches) | 89% | low |
| March Weather | 7°C (45°F) | 70 mm (2.7 inches) | 87% | moderate |
| April Weather | 10°C (50°F) | 40 mm (1.6 inches) | 85% | moderate |
| May Weather | 14°C (57°F) | 64 mm (2.5 inches) | 82% | high |
| June Weather | 18°C (65°F) | 70 mm (2.8 inches) | 82% | very high |
| July Weather | 19°C (66°F) | 82 mm (3.2 inches) | 80% | very high |
| August Weather | 19°C (66°F) | 80 mm (3.1 inches) | 76% | high |
| September Weather | 15°C (60°F) | 61 mm (2.4 inches) | 82% | moderate |
| October Weather | 12°C (55°F) | 87 mm (3.4 inches) | 89% | moderate |
| November Weather | 8°C (46°F) | 55 mm (2.2 inches) | 92% | low |
| December Weather | 6°C (43°F) | 92 mm (3.6 inches) | 92% | low |