Last updated: June 18, 2025
In Amherst, Canada, the average temperature in September hovers around 15°C (60°F). Temperatures can fluctuate from a brisk -1°C (31°F) in the cooler moments to a warm 27°C (82°F) at the highs. Expect a fair amount of rainfall with 98 mm (3.9 in) of precipitation spread over 10 days, all while enjoying a notable average humidity of 83%. Stay prepared for a variety of weather!
In September in Amherst, the average temperature is 15°C (60°F). Maximum temperatures can reach up to 27°C (82°F), while minimums can drop to as low as -1°C (31°F). It's a great time to visit, as you'll experience mild weather during the day and can prepare for cooler nights.
In Amherst in September, the total precipitation amount is 98 mm (3.9 in) recorded over a span of 10 days.
In Amherst in September humidity is 83%. With an average temperature of 15°C (60°F), this humidity feels like a damp blanket wrapping around you, making travel a bit uncomfortable and sticky, as the air clings to your skin and dampens your clothes.
In Amherst 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 Amherst.
UV Risk Categories
Weather in Amherst varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Amherst, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -5°C (23°F) | 86 mm (3.4 inches) | 82% | low |
| February Weather | -5°C (24°F) | 101 mm (4.0 inches) | 83% | moderate |
| March Weather | -2°C (29°F) | 78 mm (3.1 inches) | 82% | moderate |
| April Weather | 5°C (41°F) | 94 mm (3.7 inches) | 82% | high |
| May Weather | 10°C (49°F) | 97 mm (3.8 inches) | 82% | very high |
| June Weather | 15°C (60°F) | 94 mm (3.7 inches) | 84% | very high |
| July Weather | 19°C (66°F) | 78 mm (3.1 inches) | 86% | very high |
| August Weather | 19°C (67°F) | 78 mm (3.1 inches) | 85% | very high |
| September Weather | 15°C (60°F) | 98 mm (3.9 inches) | 83% | high |
| October Weather | 9°C (49°F) | 80 mm (3.2 inches) | 83% | moderate |
| November Weather | 3°C (38°F) | 143 mm (5.6 inches) | 85% | moderate |
| December Weather | -3°C (28°F) | 105 mm (4.1 inches) | 83% | low |