Last updated: June 24, 2025
In September, the average temperature in Oregon, United States is a pleasant 18°C (65°F). However, you might experience a range, with minimums dipping to 3°C (37°F) and maximums soaring to 33°C (92°F). Be prepared for some rain, as 120 mm (4.7 in) of precipitation is expected over the course of 10 days, and don't forget your humidity levels, averaging around 79%!
In September in Oregon, the average temperature is 18°C (65°F), with maximums that can reach 33°C (92°F) and minimums that can drop to as low as 3°C (37°F). Overall, travelers should be prepared for a range of temperatures, ensuring they pack both warm clothing for the cooler evenings and lighter attire for the hotter days.
In Oregon in September, the precipitation amount is 120 mm (4.7 in) spread over a duration of 10 days.
In Oregon in September, humidity is 79%. With an average temperature of 18°C (65°F), this humidity feels like walking through a warm mist, making traveling slightly uncomfortable and sticky, but offering a refreshing escape when you find moments of shade or a breeze.
In Oregon 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 Oregon.
UV Risk Categories
Weather in Oregon varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Oregon, focusing on differences in temperature, rainfall, humidity, and UV levels.
Temperature | Precipitation | Humidity | UV | |
---|---|---|---|---|
January Weather | -6°C (21°F) | 52 mm (2.1 inches) | 85% | moderate |
February Weather | -5°C (23°F) | 54 mm (2.1 inches) | 85% | moderate |
March Weather | 2°C (36°F) | 58 mm (2.3 inches) | 85% | moderate |
April Weather | 8°C (46°F) | 95 mm (3.7 inches) | 85% | very high |
May Weather | 15°C (60°F) | 133 mm (5.2 inches) | 78% | very high |
June Weather | 21°C (71°F) | 121 mm (4.8 inches) | 80% | very high |
July Weather | 24°C (75°F) | 84 mm (3.3 inches) | 78% | very high |
August Weather | 22°C (71°F) | 111 mm (4.4 inches) | 76% | very high |
September Weather | 18°C (65°F) | 120 mm (4.7 inches) | 79% | very high |
October Weather | 11°C (51°F) | 117 mm (4.6 inches) | 83% | moderate |
November Weather | 2°C (37°F) | 43 mm (1.7 inches) | 88% | moderate |
December Weather | -2°C (29°F) | 46 mm (1.8 inches) | 81% | low |