Last updated: June 24, 2025
In September, the average temperature in Arlington Heights, United States is a pleasant 21°C (71°F), with temperatures ranging from a cool 7°C (44°F) to a warm 35°C (95°F). Expect 81 mm (3.2 in) of precipitation over about 8 days, adding to the average humidity of 73% for a truly tropical experience.
In September in Arlington Heights, the average temperature is 21°C (71°F). Maximum temperatures can reach 35°C (95°F), while minimums can drop as low as 7°C (44°F). This makes Arlington Heights a great destination for travelers who enjoy a mix of warm days and cooler evenings.
In Arlington Heights in September, the precipitation amount is 81 mm (3.2 in) over the course of 8 days.
In Arlington Heights in September humidity is 73%. With an average temperature of 21°C (71°F), this humidity feels like a warm, enveloping blanket that can make outdoor activities a bit uncomfortable, but with proper hydration and breaks in the shade, it’s still manageable for traveling.
In Arlington Heights in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Arlington Heights.
UV Risk Categories
Weather in Arlington Heights varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Arlington Heights, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 1°C (33°F) | 80 mm (3.2 inches) | 88% | moderate |
| February Weather | 3°C (37°F) | 107 mm (4.2 inches) | 88% | moderate |
| March Weather | 7°C (45°F) | 137 mm (5.4 inches) | 87% | high |
| April Weather | 12°C (55°F) | 119 mm (4.7 inches) | 85% | very high |
| May Weather | 19°C (66°F) | 127 mm (5.0 inches) | 81% | very high |
| June Weather | 23°C (74°F) | 131 mm (5.2 inches) | 82% | very high |
| July Weather | 25°C (78°F) | 110 mm (4.3 inches) | 81% | very high |
| August Weather | 24°C (75°F) | 89 mm (3.5 inches) | 73% | very high |
| September Weather | 21°C (71°F) | 81 mm (3.2 inches) | 73% | very high |
| October Weather | 15°C (59°F) | 96 mm (3.8 inches) | 78% | high |
| November Weather | 7°C (44°F) | 99 mm (3.9 inches) | 89% | moderate |
| December Weather | 4°C (39°F) | 110 mm (4.3 inches) | 87% | moderate |