Last updated: February 24, 2025
In September, Eugene, United States, experiences a dynamic weather pattern marked by a maximum temperature soaring to 37°C (98°F), while the average hovers around a comfortable 17°C (63°F), dipping to a minimum of 4°C (39°F). With 76 mm (3.0 in) of precipitation over 6 days, the month provides a refreshing break from summer heat, contributing to a relative humidity level of 66%. This blend of warmth and occasional rain creates a vibrant atmosphere, ideal for outdoor activities and enjoying the beauty of the changing seasons.
In September, Eugene experiences a gentle transition into autumn, with temperatures that reflect the shift in seasons. The minimum temperature hovers around 4°C (39°F), providing a crispness in the air that hints at the cooler months ahead. The average temperature stabilizes at a comfortable 17°C (63°F), perfect for outdoor activities as summer fades. Interestingly, daytime highs can still reach a warm 37°C (98°F), reminiscent of summer's lingering warmth, allowing for some balmy days. This combines to create a charming atmosphere where early fall's coolness invites cozy sweaters, while the occasional warm spell offers a reminder of summer's end. As October approaches, the gradual cooling trend continues, making September a delightful blend of seasons.
In September, Eugene experiences a noticeable uptick in precipitation, receiving 76 mm (3.0 in) over 6 days. This marks a shift from the notably dry months of July and August, where rainfall was scarce, totaling a mere 2 mm and 5 mm respectively. With the arrival of fall, the city's weather begins to embrace the moisture typical of its Pacific Northwest climate. This transition is reflected in September's precipitation, which serves as a precursor to the wetter months ahead, setting the stage for an increase in both the amount and frequency of rain as the season progresses. As the outlook turns more autumnal, the rhythm of rain reestablishes itself, ushering in the lush landscapes that Eugene is known for.
In September, Eugene experiences a notable shift in humidity, reaching 66%, the lowest level for the month and just a notch below August's 67%. This decrease signals the transition into the fall season, following a summer of relatively lower humidity levels compared to the earlier months in the year, which consistently exceeded 80%. As the year progresses, humidity begins to rise again in October, indicating that Eugene's maritime climate continues to be marked by significant seasonal shifts, with a return to the moister conditions typical of the late fall and winter months.
In September, Eugene experiences a UV Index of 8, which falls into the very high exposure category, marking a slight decline from the peak of 10 seen during the summer months of May through August. With a burn time of just 15 minutes, it's crucial to take precautions, especially as the sunlight remains strong, inviting outdoor activities. This trend underscores the importance of sun safety as summer transitions into fall. As we move into October, the UV Index will decrease to 5, shifting back to a moderate exposure level. For more details on UV levels throughout the year, visit Eugene UV Index.
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As summer fades into autumn, September in Eugene offers a delightful balance of warmth and light, boasting 281 hours of sunshine—a generous amount that surpasses the earlier months of the year. The sunlit days of September still reflect the vibrant energy of summer, with daylight hours tapering off from the peak of July at 394 hours. This month experiences a gradual decline in sunshine, yet it remains a notable highlight compared to the overcast days that will emerge in the later fall months. As nature transitions, residents can enjoy cool evenings but still savor the warmth of the sun, making September a perfect time for outdoor activities amidst the stunning landscapes of Eugene.
September in Eugene sees a significant likelihood of sunny weather, boasting a 63% chance of sunshine. This figure aligns with the positive trend established during the summer months, where July and August unveil the region's sunniest days, reaching peaks of 84% and 70% respectively. As the city transitions into fall, September maintains a strong prospect of clear skies, making it an ideal time for outdoor activities before the cloudy and rainy months settle in. Notably, the chances of sunny weather begin a noticeable decline in October, dipping to just 29%, reinforcing the value of enjoying the last warm rays of sunshine in September.
As summer gives way to autumn, September in Eugene marks a gentle transition in daylight duration. With 12 hours of daylight, the days are still pleasantly long, inviting outdoor activities as the season changes. This month witnesses a gradual decline from the peak of 15 hours experienced in June and July, signaling the approach of shorter days ahead. As the year progresses into October, daylight will dwindle further, dipping to 10 hours. The shift in daylight not only influences the daily rhythm but also enriches the landscape with the vibrant hues of fall, creating a picturesque backdrop for residents and visitors alike.
As September ushers in the gentle transition toward autumn in Eugene, the average wind speed hovers around 2.1 m/s (5 mph), paralleling the consistent breezy nature of the preceding summer months. The wind demonstrates a subtle drop from the summer peak but maintains a steady rhythm that's characteristic of this time of year. Throughout the months, wind speeds exhibit a mild fluctuation, with the highest gusts occurring in December at 2.4 m/s (5 mph), while the spring months generally experience slightly calmer breezes. This steady wind flow in September not only enhances the city's picturesque fall scenery but also invites residents and visitors alike to enjoy outdoor activities amidst the crisp, fresh air.
The weather in Eugene changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Eugene and find detailed weather information for every month.
September and January present significantly different weather conditions. In September, temperatures can range from a cool 4°C (39°F) at night to a warm 37°C (98°F) during the day, with an average temperature of 17°C (63°F). This month sees a moderate amount of precipitation at 76 mm (3.0 in) across about 6 days and a humidity level of 66%. In contrast, January is much colder, with temperatures dropping as low as -12°C (11°F) and averaging just 5°C (42°F), peaking at 18°C (65°F). Additionally, January experiences higher precipitation at 152 mm (6.0 in) spread over 15 days, along with increased humidity at 84%. For more detailed information about January weather, you can visit Eugene weather in January.
When comparing the weather in September and February, notable differences emerge. September tends to be warmer with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 37°C (98°F), featuring an average of 17°C (63°F). In contrast, February showcases a cooler climate, with temperatures ranging from -6°C (21°F) to a maximum of 19°C (67°F), averaging just 5°C (41°F). Precipitation levels also vary significantly; September experiences 76 mm (3.0 in) over 6 days, while February sees a much wetter climate with 197 mm (7.7 in) spread across 18 days. Additionally, the humidity in February is noticeably higher at 85%, compared to September's 66%. For further details on the February weather, you can check out Eugene weather in February.
When comparing the weather in September and March, significant differences are evident. September offers a warmer climate with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 37°C (98°F) and an average of 17°C (63°F). It also experiences lower humidity at 66% and less precipitation, averaging 76 mm (3.0 in) over just six days. In contrast, March features much cooler temperatures, with lows dipping to -7°C (20°F) and highs reaching up to 23°C (74°F), leading to a lower average of 7°C (45°F). This month is notably wetter, receiving 139 mm (5.5 in) of rainfall over 16 days and higher humidity levels at 86%. For more details, you can check Eugene weather in March.
September and April showcase distinct weather patterns, reflecting the transition from summer to fall and the onset of spring, respectively. In September, temperatures can range from a cool 4°C (39°F) to a hot 37°C (98°F), with an average of 17°C (63°F). The month experiences relatively moderate precipitation of 76 mm (3.0 in) over approximately 6 days and maintains a humidity level of 66%.
In contrast, April features cooler temperatures, with a minimum of -2°C (29°F) and a maximum of 28°C (83°F), averaging around 10°C (50°F). This month tends to be wetter, with a total of 134 mm (5.3 in) of rainfall spread over 14 days, while humidity is higher at 83%. For more detailed insights on the weather in April, you can visit Eugene weather in April.
September and May present distinctly different weather patterns. In September, temperatures can swing widely, with a minimum of 4°C (39°F) and a maximum reaching up to 37°C (98°F), averaging around 17°C (63°F). The month experiences 76 mm (3.0 in) of precipitation over about 6 days, with humidity around 66%. In contrast, May is generally cooler, with a minimum of 1°C (34°F) and a maximum of 29°C (85°F), averaging 13°C (57°F). Precipitation in May is slightly lower at 62 mm (2.5 in) but occurs over 9 days, contributing to a higher humidity level of 83%. For more detailed information about the weather in May, visit Eugene weather in May.
In comparing the weather of September and June, we see some notable differences. September boasts a minimum temperature of 4°C (39°F) and a maximum of 37°C (98°F), with an average temperature around 17°C (63°F). It experiences more rainfall, with total precipitation measuring 76 mm (3.0 in) over 6 days at a humidity level of 66%. In contrast, June has slightly cooler nights with a minimum temperature of 5°C (42°F) but can reach a significantly higher maximum of 44°C (111°F). The month also sees less precipitation, totaling 41 mm (1.6 in) over the same number of days, but has higher humidity at 83%. For a more detailed look at June weather, you can check Eugene weather in June.
In comparing the weather of September and July, September experiences a broader temperature range, with minimums dipping to 4°C (39°F) and an average temperature of 17°C (63°F), while July maintains milder minimums at 7°C (45°F) and a higher average of 20°C (69°F). Both months can reach similar maximum temperatures of 37°C (98°F in September and 99°F in July), but July is significantly drier with only 2 mm (0.1 in) of precipitation across zero days, compared to September's 76 mm (3.0 in) over six days. Additionally, humidity levels are higher in July at 78%, compared to 66% in September, indicating a more humid feeling during the earlier summer month. For more details, check Eugene weather in July.
In comparing the weather between August and September, we see a notable shift in temperature and precipitation patterns. August tends to be warmer, with an average temperature of 21°C (69°F) and occasional highs reaching up to 40°C (104°F). It has minimal rainfall, only 5 mm (0.2 in) over just one day, contributing to a drier month. In contrast, September experiences a broader temperature range, with a minimum of 4°C (39°F) and an average of 17°C (63°F), peaking at 37°C (98°F). This month also sees increased precipitation, totaling 76 mm (3.0 in) over six days, and a humidity level of 66%. For a detailed look at August's weather, you can check out Eugene weather in August.
September tends to be warmer than October, with average temperatures reaching up to 17°C (63°F) and maximums peaking at 37°C (98°F). In contrast, October sees a cooler average temperature of 11°C (53°F), with a minimum dropping to -4°C (25°F). Additionally, October experiences more precipitation, with 99 mm (3.9 in) over 10 days, compared to September's 76 mm (3.0 in) over just 6 days. The humidity also increases, rising from 66% in September to 77% in October. For more details on October weather, you can check Eugene weather in October.
September and November present strikingly different weather patterns. September typically offers a mild climate, with average temperatures around 17°C (63°F) and highs peaking at 37°C (98°F), while experiencing relatively low precipitation of 76 mm (3.0 in) over about 6 days. In contrast, November sees a significant drop in temperature with an average of 8°C (46°F), and maximum temperatures reaching only 21°C (70°F). This month also brings increased rainfall, totaling 141 mm (5.6 in) over 14 days, along with higher humidity levels at 87%. For more details, you can check out Eugene weather in November.
In September, the weather is characterized by warmer temperatures, with a minimum of 4°C (39°F) and an average of 17°C (63°F), peaking at a high of 37°C (98°F). This month experiences moderate precipitation at 76 mm (3.0 in), occurring over about 6 days, and has a humidity level of 66%. In contrast, December presents a much cooler climate, featuring a minimum temperature of -6°C (21°F) and an average of 5°C (41°F), with a maximum of 18°C (65°F). Rainfall is significantly higher at 180 mm (7.1 in), spread across 18 days, and humidity increases to 87%. For more details on the colder season, check out Eugene weather in December.
As summer transitions to autumn, September in Eugene brings a delightful blend of warm days and cooler nights. While the maximum temperature can reach up to a steamy 37°C (98°F), the overall climate shifts, offering an average that offers relief with comfortable 17°C (63°F) days. Unlike the heavier rains of winter months, September experiences a modest amount of precipitation, with just six days of rainfall, making it a relatively dry month. The humidity hovers around 66%, contributing to a crispness in the air that heralds the coming fall. For more insights into the seasonal patterns and weather variations, explore Eugene Climate.