Last updated: June 24, 2025
In September, the average temperature in Maine, United States hovers around 16°C (61°F). Expect a wide temperature range, with minimums dipping to 0°C (32°F) and maximums soaring to 32°C (90°F). Throughout the month, precipitation totals about 83 mm (3.3 in), typically falling over 10 days. The air is quite humid, with an average humidity level of 78%.
In September in Maine, the average temperature is 16°C (61°F). The maximum can reach 32°C (90°F) and the minimum can be as low as 0°C (32°F). Be prepared for a diverse range of weather conditions while traveling, as it can vary significantly from warm days to chilly nights.
In Maine in September, the total precipitation amount is 83 mm (3.3 in) over a span of 10 days.
In Maine in September, humidity is 78%. With an average temperature of 16°C (61°F), this humidity feels like a warm, sticky embrace, making travel somewhat uncomfortable as it clings to your skin and creates a heavy atmosphere that can drain your energy.
In Maine 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 Maine.
UV Risk Categories
Weather in Maine varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Maine, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -9°C (17°F) | 34 mm (1.3 inches) | 89% | low |
| February Weather | -8°C (17°F) | 50 mm (2.0 inches) | 90% | moderate |
| March Weather | -1°C (31°F) | 53 mm (2.1 inches) | 87% | moderate |
| April Weather | 5°C (42°F) | 98 mm (3.9 inches) | 84% | high |
| May Weather | 13°C (56°F) | 103 mm (4.1 inches) | 77% | very high |
| June Weather | 19°C (67°F) | 102 mm (4.0 inches) | 75% | very high |
| July Weather | 22°C (71°F) | 117 mm (4.6 inches) | 74% | very high |
| August Weather | 19°C (67°F) | 121 mm (4.8 inches) | 73% | very high |
| September Weather | 16°C (61°F) | 83 mm (3.3 inches) | 78% | high |
| October Weather | 8°C (47°F) | 109 mm (4.3 inches) | 84% | moderate |
| November Weather | 0°C (32°F) | 50 mm (2.0 inches) | 89% | moderate |
| December Weather | -5°C (23°F) | 52 mm (2.1 inches) | 87% | low |