Last updated: June 24, 2025
In September, the average temperature in Round Lake Heights, United States hovers around 19°C (67°F), with comfortable highs reaching 29°C (84°F) and cooler lows dipping to 6°C (43°F). Expect around 84 mm (3.3 in) of precipitation spread over approximately 10 days, contributing to an average humidity of 79% that enhances the lushness of the landscape.
In September in Round Lake Heights, the average temperature is 19°C (67°F). Maximums can reach 29°C (84°F) while minimums can drop as low as 6°C (43°F). This makes Round Lake Heights an ideal destination for travelers seeking a mix of mild and warm weather during this time of year.
In Round Lake Heights in September, the precipitation amount is 84 mm (3.3 in) over a span of 10 days.
In Round Lake Heights in September, humidity is 79%. With an average temperature of 19°C (67°F), this humidity feels like a warm, enveloping blanket that makes traveling a bit more challenging, as the air is thick and can leave you feeling sluggish during outdoor adventures.
In Round Lake 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 Round Lake Heights.
UV Risk Categories
Weather in Round Lake Heights varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Round Lake Heights, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -4°C (26°F) | 67 mm (2.7 inches) | 85% | low |
| February Weather | -3°C (27°F) | 65 mm (2.6 inches) | 85% | moderate |
| March Weather | 2°C (36°F) | 70 mm (2.8 inches) | 85% | high |
| April Weather | 6°C (44°F) | 113 mm (4.5 inches) | 85% | very high |
| May Weather | 12°C (54°F) | 156 mm (6.1 inches) | 78% | very high |
| June Weather | 18°C (66°F) | 100 mm (3.9 inches) | 80% | very high |
| July Weather | 22°C (73°F) | 74 mm (2.9 inches) | 78% | very high |
| August Weather | 22°C (72°F) | 72 mm (2.8 inches) | 76% | very high |
| September Weather | 19°C (67°F) | 84 mm (3.3 inches) | 79% | very high |
| October Weather | 12°C (54°F) | 130 mm (5.1 inches) | 83% | moderate |
| November Weather | 4°C (39°F) | 56 mm (2.2 inches) | 88% | moderate |
| December Weather | 0°C (33°F) | 58 mm (2.3 inches) | 81% | low |