Last updated: June 18, 2025
In September, the average temperature in Rock Island, Canada hovers around 14°C (58°F), with potential extremes ranging from a chilly -4°C (26°F) to a warm 29°C (85°F). Expect about 83 mm (3.3 in) of precipitation over 9 days, contributing to an average humidity of 77%. Prepare for a mix of cool breezes and occasional rainfall!
In September in Rock Island, the average temperature is 14°C (58°F). Maximums can reach 29°C (85°F), while minimums can drop as low as -4°C (26°F). This variation makes it advisable to pack layers and be prepared for both warm and chilly weather while traveling.
In Rock Island in September, the precipitation amount is 83 mm (3.3 in) over the course of 9 days.
In Rock Island in September, humidity is 77%. With an average temperature of 14°C (58°F), this humidity feels like a warm blanket wrapping around you, making traveling feel sticky and heavy, yet still manageable as you explore the sights.
In Rock Island in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Rock Island.
UV Risk Categories
Weather in Rock Island varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Rock Island, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -8°C (17°F) | 88 mm (3.5 inches) | 91% | low |
| February Weather | -7°C (20°F) | 82 mm (3.2 inches) | 89% | moderate |
| March Weather | -3°C (27°F) | 80 mm (3.1 inches) | 85% | moderate |
| April Weather | 5°C (40°F) | 112 mm (4.4 inches) | 84% | high |
| May Weather | 12°C (53°F) | 103 mm (4.1 inches) | 78% | very high |
| June Weather | 17°C (62°F) | 116 mm (4.5 inches) | 72% | very high |
| July Weather | 20°C (67°F) | 119 mm (4.7 inches) | 75% | very high |
| August Weather | 19°C (66°F) | 104 mm (4.1 inches) | 74% | very high |
| September Weather | 14°C (58°F) | 83 mm (3.3 inches) | 77% | high |
| October Weather | 8°C (47°F) | 149 mm (5.9 inches) | 85% | moderate |
| November Weather | 0°C (33°F) | 114 mm (4.5 inches) | 86% | moderate |
| December Weather | -5°C (23°F) | 84 mm (3.3 inches) | 85% | low |