Last updated: February 24, 2025
September in Sunriver, United States, showcases a diverse climate that blends warm days with crisp evenings. The month boasts a maximum temperature reaching 36°C (97°F), creating opportunities for outdoor activities, while the average temperature settles at a comfortable 14°C (57°F). As the nights cool, temperatures may dip to a minimum of -3°C (26°F), adding a refreshing chill to the air. With 39 mm (1.5 in) of rainfall spread over five days, this period sees a modest level of precipitation, contributing to the lush beauty of the region. The humidity, averaging 57%, balances the warmth, making September an invigorating and pleasant time to experience the natural splendor of Sunriver.
In September, Sunriver experiences a delightful transition as summer begins to fade, with temperatures showcasing a notable range. The month opens with a minimum temperature of -3°C (26°F), while the daytime warmth peaks at an impressive 36°C (97°F), allowing for a pleasant balance between cool mornings and warm afternoons. With an average temperature of 14°C (57°F), September offers a comfortable climate ideal for outdoor activities, paving the way for vibrant autumn hues. This month starkly contrasts the icy depths of January, highlighting a significant seasonal shift that invites both locals and visitors to relish the beauty of nature before winter sets in.
In September, Sunriver experiences a noticeable uptick in precipitation, totaling 39 mm (1.5 in) over 5 days, marking a shift from the drier summer months of July and August. This increase signifies the onset of fall, as sunlight gives way to refreshing rain, preparing the landscape for the vibrant colors of autumn. While July recorded a mere 10 mm across just 2 days, September's moisture provides a much-needed relief, hinting at the seasonal transition. As precipitation levels continue to rise into the fall, with October seeing a likely increase to 46 mm, residents can anticipate a refreshingly crisp atmosphere, invigorated by nature's changes.
As the year progresses in Sunriver, United States, September stands out as a transitional month with a notable drop in humidity to 57%, marking the lowest level compared to the more humid months earlier in the year. Following the peak humidity levels of 87% in the winter months—from January through March—and a gradual decrease through to August, which sees 60%, September signals a refreshing shift towards drier air. This trend hints at the approach of autumn, as humidity begins to rise again in October at 76%. The gentle decline in humidity throughout the summer and the significant dip in September create a delightful outdoor atmosphere, perfect for enjoying Sunriver's natural beauty.
September in Sunriver, United States, marks a transition from the peak summer UV levels to slightly diminished but still significant exposure. With a UV Index of 8, categorized as very high, residents and visitors are advised to take care, as the burn time drops to just 15 minutes. This trend reflects a gradual decrease from the extreme UV levels of 11 seen in May and June, yet September still demands vigilance when enjoying outdoor activities. As the sun begins to lower in the sky, remember to stay protected and monitor UV conditions regularly for safe sun exposure. For detailed information on UV levels throughout the year, check out the Sunriver UV Index.
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As summer gracefully transitions into fall, September in Sunriver shines brightly with an impressive 299 hours of sunshine, a splendid conclusion to a season of warmth. The trend throughout the year reveals a significant increase from the chilly 113 hours in January, reaching a peak of 409 hours in July. While September may see a decline from the sultry August days, it still enjoys ample sunlight, surpassing the earlier spring months of April and May. The gradual tapering of daylight as autumn approaches paints a picturesque backdrop for outdoor adventures, making it an ideal time for visitors to soak in the last rays of summer before the cozy months ahead.
As September rolls into Sunriver, the likelihood of enjoying sunny weather remains quite favorable, boasting a 70% chance of sunshine. This marks a slight dip from the peak summer months of July and August, which experience 82% and 75% chances of clear skies, respectively. The transition into fall brings cooler temperatures, yet the remnants of summer keep the sun shining brightly compared to the winter months, where probabilities plummet to a mere 15% in December. Overall, September continues the trend of summer's warmth, making it an ideal time for outdoor activities before the cooler days set in.
As summer gives way to autumn in Sunriver, September offers a gentle decline in daylight, with about 12 hours of sunshine each day. Following the peak days of 15 hours in June and July, the transition into fall is marked by shorter daylight hours, yet it remains more generous than both the spring's early months and the winter's stark limitations. This gradual decrease in daylight resonates with the changing seasons, creating an inviting atmosphere for outdoor activities while the crisp air begins to set in. As we move towards October and November, the daily light continues to diminish, enhancing the cozy ambiance that autumn brings to this serene locale.
As summer transitions into autumn, September in Sunriver brings a gentle breeze with an average wind speed of 2.2 m/s (5 mph), mirroring the calmness of August. This subtle shift marks a continuation of decreasing wind patterns observed since July, where a notable peak of 3.5 m/s in February has steadily dwindled. The month’s tranquil winds create a picturesque backdrop, encouraging outdoor enthusiasts to revel in the vibrant early fall surroundings. With gusts picking up slightly in October, the wind in September offers a serene yet invigorating atmosphere, perfect for leisurely explorations within this stunning landscape.
The weather in Sunriver 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 Sunriver and find detailed weather information for every month.
September and January present stark contrasts in weather conditions. In September, temperatures range from a brisk -3°C (26°F) at night to a warm 36°C (97°F) during the day, with an average of 14°C (57°F). The month experiences relatively low precipitation at 39 mm (1.5 in) over about 5 days, coupled with a comfortable humidity level of 57%. In sharp contrast, January is much colder, with temperatures dropping to a minimum of -23°C (-9°F) and peaking at only 12°C (53°F), averaging around 0°C (32°F). It is also wetter, with precipitation totaling 95 mm (3.7 in) falling over 13 days and a higher humidity of 87%. For further details on January weather patterns, you can check Sunriver weather in January.
September and February present a stark contrast in weather conditions. In September, temperatures range from a chilly -3°C (26°F) at night to a warm 36°C (97°F) during the day, with an average temperature of 14°C (57°F). The month experiences relatively low precipitation of 39 mm (1.5 in) over about 5 days and a humidity level of 57%. In contrast, February is much colder, with temperatures dipping as low as -24°C (-11°F) and peaking at just 16°C (61°F), averaging -1°C (31°F). This month sees significantly higher precipitation at 114 mm (4.5 in) across 16 days, accompanied by increased humidity levels of 87%. For more specific details on February weather, visit Sunriver weather in February.
In September, temperatures can range from a chilly -3°C (26°F) at night to a scorching 36°C (97°F) during the day, with an average of 14°C (57°F). The month sees relatively limited rainfall, totaling 39 mm (1.5 in) over approximately 5 days, and humidity levels are moderate at 57%. In contrast, March presents a much cooler climate with minimum temperatures dropping to -14°C (6°F) and an average of just 2°C (36°F), peaking at 18°C (65°F). This month experiences more precipitation at 74 mm (2.9 in) spread over 14 days, alongside a higher humidity of 87%. For a detailed look at the weather in March, check out Sunriver weather in March.
When comparing the weather in September and April, distinct differences emerge. September experiences a wider temperature range, with minimums as low as -3°C (26°F) and maximums reaching up to 36°C (97°F), leading to an average temperature of 14°C (57°F). In contrast, April has colder minimums at -11°C (12°F) and a significantly lower maximum of 26°C (79°F), resulting in an average of just 5°C (42°F). Additionally, April tends to be wetter, with 69 mm (2.7 in) of precipitation over 11 days, compared to September's 39 mm (1.5 in) over 5 days. The humidity levels also differ, with April being considerably more humid at 86%, while September sits at 57%. For more specifics on April weather, check out Sunriver weather in April.
September and May present contrasting weather patterns. In September, the temperature ranges from a minimum of -3°C (26°F) to a maximum of 36°C (97°F), with an average of 14°C (57°F). The month experiences relatively low precipitation at 39 mm (1.5 in) over about 5 days, and humidity sits at a moderate 57%. In contrast, May typically has a lower temperature range, with lows of -5°C (24°F) and highs reaching 30°C (86°F), averaging around 10°C (50°F). Precipitation is slightly higher at 46 mm (1.8 in) spread over 10 days, contributing to a significantly higher humidity level of 79%. For those interested in a detailed look at May weather, visit Sunriver weather in May.
In comparing the weather of September and June, we see notable differences in temperature and humidity levels. September features a wider temperature range with a minimum of -3°C (26°F), an average of 14°C (57°F), and a maximum of 36°C (97°F), accompanied by a moderate precipitation level of 39 mm (1.5 in) over five days at a humidity of 57%. In contrast, June has slightly warmer temperatures, with a minimum of -2°C (29°F), an average of 15°C (58°F), and a peak of 40°C (104°F). June also experiences a bit more rainfall at 29 mm (1.2 in) over seven days but has higher humidity at 80%. For more detailed insights on June weather, you can check Sunriver weather in June.
When comparing the weather of September and July, several notable differences emerge. September experiences a broader temperature range, with minimums as low as -3°C (26°F) and maximums soaring up to 36°C (97°F), averaging around 14°C (57°F). In contrast, July maintains milder temperatures, with a minimum of 0°C (32°F) and an average of 19°C (67°F), peaking at 35°C (95°F). Precipitation is also notably higher in September, with 39 mm (1.5 in) over five days, while July only sees 10 mm (0.4 in) across two days, resulting in lower humidity levels in September at 57%, compared to July's 77%. For more specifics on July weather conditions, you can refer to this link: Sunriver weather in July.
In comparing the weather between September and August, September experiences a broader temperature range, with minimums dropping to -3°C (26°F) and maximums reaching up to 36°C (97°F). This contrasts with August, where temperatures are milder, ranging from a minimum of 0°C (32°F) to a maximum of 36°C (98°F). While September sees an increase in precipitation with 39 mm (1.5 in) over 5 days, August is drier, with only 15 mm (0.6 in) over 4 days. Humidity levels are slightly lower in September at 57%, compared to August's 60%. For more detailed information on August weather, you can check out Sunriver weather in August.
In September, temperatures in the region range from a minimum of -3°C (26°F) to a maximum of 36°C (97°F), with an average temperature of 14°C (57°F). This month receives about 39 mm (1.5 in) of precipitation over five days, and humidity levels hover around 57%. Conversely, October experiences cooler conditions, with minimum temperatures dropping to -10°C (14°F) and an average of 7°C (45°F). The maximum temperature in October reaches 29°C (84°F), and precipitation increases slightly to 46 mm (1.8 in) over six days, with humidity rising to 76%. For a detailed look at the weather in this month, you can visit Sunriver weather in October.
In September, the weather features a wide temperature range, with minimums dipping to -3°C (26°F) and maximums soaring to a warm 36°C (97°F), resulting in an average temperature of 14°C (57°F). The month sees relatively low precipitation at 39 mm (1.5 in) over just 5 days, along with a moderate humidity level of 57%. In contrast, November brings a chillier atmosphere, with temperatures dropping significantly—minimums reach -17°C (1°F) and maximums only reach 21°C (70°F), leading to a much lower average of 3°C (37°F). Additionally, November experiences increased precipitation totaling 79 mm (3.1 in) over 11 days, accompanied by a higher humidity level of 87%. For a closer look at the weather specifics in that month, you can visit Sunriver weather in November.
September and December present markedly different weather conditions. In September, temperatures can fluctuate dramatically, ranging from a chilly -3°C (26°F) to a scorching high of 36°C (97°F), with an average temperature of 14°C (57°F). The month sees relatively low precipitation, only 39 mm (1.5 in) over about 5 days and a humidity level of 57%. In contrast, December is much colder, with minimum temperatures plunging to -17°C (2°F) and an average of 0°C (31°F). The maximum temperature rarely exceeds 17°C (63°F), and the month is considerably wetter, with 91 mm (3.6 in) of precipitation spread over 14 days and a high humidity level of 88%. For more detailed insights on December weather, you can visit Sunriver weather in December.
As summer transitions to fall, September in Sunriver presents a delightful blend of warm days and cool nights, marking a shift from the peak temperatures of summer. With an average chill in the air and the occasional rainfall, this month offers a refreshing contrast to the dry and sweltering days of the preceding months. Humidity settles comfortably around 57%, creating an inviting atmosphere for outdoor activities. While some rain may sprinkle the landscape, it usually adds to the serene beauty of the surroundings. For a more detailed look at what to expect throughout the year, check out the Sunriver Climate.