Last updated: June 24, 2025
In Arlington Heights, United States, the average temperature in September hovers around 19°C (66°F), with a minimum dipping to 3°C (37°F) and a maximum soaring to 32°C (90°F). Expect about 120 mm (4.7 in) of precipitation across 10 days, paired with an average humidity level of 66%. This combination makes for a vibrant yet varied climate, perfect for those seeking both warmth and a touch of rain.
In September in Arlington Heights, the average temperature is 19°C (66°F). Maximum temperatures can reach 32°C (90°F), while minimum temperatures can drop to as low as 3°C (37°F). Be sure to pack a variety of clothing to accommodate both warm and cool weather during your travels.
In Arlington Heights in September, the precipitation amount is 120 mm (4.7 in) spread over a duration of 10 days.
In Arlington Heights in September, humidity is 66%. With an average temperature of 19°C (66°F), this humidity feels like a warm, cozy embrace, creating an inviting atmosphere for exploring the local sights while ensuring you stay hydrated and comfortable throughout your adventures.
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 (30°F) | 76 mm (3.0 inches) | 87% | moderate |
| February Weather | 0°C (33°F) | 109 mm (4.3 inches) | 85% | moderate |
| March Weather | 3°C (39°F) | 97 mm (3.8 inches) | 85% | high |
| April Weather | 10°C (49°F) | 120 mm (4.7 inches) | 83% | very high |
| May Weather | 15°C (60°F) | 144 mm (5.7 inches) | 75% | very high |
| June Weather | 20°C (69°F) | 106 mm (4.2 inches) | 73% | very high |
| July Weather | 24°C (75°F) | 139 mm (5.5 inches) | 65% | very high |
| August Weather | 22°C (72°F) | 146 mm (5.7 inches) | 62% | very high |
| September Weather | 19°C (66°F) | 120 mm (4.7 inches) | 66% | very high |
| October Weather | 13°C (56°F) | 143 mm (5.6 inches) | 79% | high |
| November Weather | 5°C (42°F) | 95 mm (3.7 inches) | 87% | moderate |
| December Weather | 1°C (34°F) | 112 mm (4.4 inches) | 85% | low |