Last updated: February 24, 2025
In Chelan, United States, September weather showcases a delightful transition, with maximum temperatures peaking at 35°C (96°F), while the average rests comfortably at 16°C (61°F). The minimum dips to a brisk 2°C (36°F), perfect for those who enjoy cooler evenings. Despite the warmth, the month sees a modest 23 mm (0.9 in) of precipitation across just three days, keeping humidity around a moderate 62%. This blend of temperatures and light rainfall creates an inviting atmosphere for outdoor activities and exploration in this scenic region.
In September, Chelan experiences a delightful transition from the sweltering summer heat to milder autumn temperatures. As the month unfolds, the average temperature sits around 16°C (61°F), offering a comfortable respite after the peak summer highs. With a minimum of 2°C (36°F) and a maximum of 35°C (96°F), the days begin to cool, yet afternoons can still feel quite warm and inviting. This month marks a shift in climate, showcasing a gradual decline in temperatures as the region prepares for the chillier months ahead. The balance of warm days and crisp evenings makes September a particularly charming time to explore Chelan's stunning landscapes.
In September, Chelan experiences a noticeable uptick in precipitation, accumulating 23 mm (0.9 in) over three days of rain, marking a transition as summer fades into fall. This increase follows an exceptionally dry summer, with July and August recording minimal rainfall. The month's precipitation paves the way for the wetter months ahead, with October's average jumping to 48 mm (1.9 in), creating a stark contrast to the dry heat of the preceding months. As the landscape shifts with the arrival of autumn, September serves as a gentle reminder of the changing seasons, offering residents a refreshing respite from the summer's dry spell.
As summer transitions into fall, September in Chelan experiences a noticeable dip in humidity, dropping to a comfortable 62%. This marks a continuation of the decreasing trend seen from the peak August humidity of 63%, making it one of the driest months of the year. The fluctuation throughout the year reveals a pattern where the winter months maintain high humidity levels, averaging around 86%, while the summer months see a gradual decline. As autumn approaches, the humidity begins to creep back up, with October bringing a rise to 83%. Overall, September serves as a sweet spot, offering a brief respite from the region's otherwise high humidity levels, setting the stage for the crisp, refreshing days of fall ahead.
As September rolls into Chelan, the UV Index takes a slight dip to 7, categorizing exposure as high and suggesting a burn time of around 25 minutes for fair-skinned individuals. This transition reflects a gradual decline from the peak indices of summer, where values soared to 10 in July and 9 in August, both classified as very high exposure risks. Interestingly, September marks a notable shift while still allowing for ample time outdoors; it serves as a reminder to remain vigilant as the sun's intensity persists. With clear skies typical of this season, residents and visitors should be mindful of the lingering risks. For more information on UV levels in your area, check out Chelan UV Index.
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September in Chelan, United States, is a delightful transition from the vibrant summer months, basking in a generous 287 hours of sunshine. Following July's peak of 416 hours, the sun begins to mellow, yet the warm days linger, inviting residents and visitors alike to enjoy the spectacular autumn scenery. As summer fades into fall, the sunlight gradually decreases, echoing the gradual drop that starts with August's 360 hours and continues into the cooler months. This trend underscores Chelan's appeal as a destination that offers a glorious farewell to summer warmth, while setting the stage for the crisp beauty of October and beyond.
September in Chelan marks a transition towards fall, with the likelihood of sunny weather still holding a respectable 53%. This places it comfortably above the average for the early months of the year, reflecting a continuation of summer's warmth as the bustling season begins to wane. After basking in the abundant sunshine of July, which boasts an impressive 87% chance of clear skies, and the slightly diminished yet still bright August at 65%, September shows a notable drop while still enjoying more sunny days than many earlier months. As the days grow shorter, visitors can expect a pleasant blend of warmth and crisp air, making it an ideal time for outdoor activities amidst the stunning fall colors.
In September, Chelan welcomes the gradual yet noticeable shift in daylight, offering about 12 hours of sunlight each day. This marks a subtle decline from the 14 hours experienced in August, signaling the transition towards autumn. Throughout the year, Chelan has witnessed a compelling rhythm of daylight that peaks in the summer months, with 15 hours of sun in both June and July. As we move into the fall, daylight begins to dwindle, starting a cycle that will lead to the cozy, shorter days of winter. The changing lengths of daylight not only highlight the beauty of the seasons but also invite residents and visitors alike to savor the warm, sunlit days of September before the coolness of October arrives.
In September, the wind in Chelan gently whispers at an average speed of 1.9 m/s (4 mph), marking a slight decrease from the summer months. Throughout the year, wind speeds show a steady rise from the start of the year, peaking in May at 2.6 m/s (6 mph). Following the warmer months, the winds gradually decline, creating a tranquil atmosphere as autumn approaches. This transition reflects a consistent seasonal pattern, where late summer breezes soften into lighter gusts, inviting locals and visitors alike to enjoy the serene beauty of Chelan's landscape.
The weather in Chelan 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 Chelan and find detailed weather information for every month.
September and January present strikingly different weather patterns. In September, temperatures range from a chilly minimum of 2°C (36°F) to a warm maximum of 35°C (96°F), with an average of 16°C (61°F). This month experiences relatively low precipitation at 23 mm (0.9 in) over just three days and a moderate humidity level of 62%. In contrast, January brings much colder temperatures, with a minimum of -17°C (1°F) and a maximum of only 7°C (45°F), averaging -2°C (28°F). Precipitation increases significantly to 76 mm (3.0 in) over 13 days, accompanied by higher humidity at 86%. For more details on January's weather, you can check out Chelan weather in January.
September and February offer starkly contrasting weather patterns. In September, temperatures range from a mild 2°C (36°F) to a warm 35°C (96°F), with an average of 16°C (61°F) and relatively low humidity at 62%. This month sees around 23 mm (0.9 in) of precipitation over just three days, making it a drier time of year. In contrast, February experiences much colder temperatures, ranging from a chilly -14°C (6°F) to a pleasant maximum of 12°C (55°F), with an average of -2°C (29°F). The month is wetter, featuring 62 mm (2.4 in) of precipitation across 11 days and higher humidity at 86%. For a detailed look at February weather specifics, you can check out Chelan weather in February.
In September, the weather tends to be warmer, with temperatures ranging from a minimum of 2°C (36°F) to a maximum of 35°C (96°F), averaging around 16°C (61°F). The month experiences relatively low precipitation of 23 mm (0.9 in) over just three days and has a moderate humidity level of 62%.
Conversely, March brings cooler temperatures, with a minimum of -15°C (6°F) and a maximum of 18°C (64°F), averaging only 3°C (38°F). It is also wetter, with 41 mm (1.6 in) of precipitation over eight days and a higher humidity of 87%. For a detailed look at weather patterns, you can visit Chelan weather in March.
In comparing the weather of September and April, significant differences emerge in temperature and precipitation. September showcases a wider temperature range with a minimum of 2°C (36°F) and a maximum reaching up to 35°C (96°F), resulting in an average of 16°C (61°F). Conversely, April is cooler overall, with temperatures ranging from a low of -4°C (25°F) to a high of 25°C (76°F) and an average of just 8°C (47°F). Additionally, April experiences more frequent rainfall, with 36 mm (1.4 in) over six days compared to only 23 mm (0.9 in) over three days in September. The higher humidity in April, at 84%, also contrasts sharply with September's relatively lower humidity of 62%. For more detailed insights, you can explore Chelan weather in April.
September and May present contrasting weather patterns. In September, temperatures range from a brisk 2°C (36°F) at night to a warm 35°C (96°F) during the day, with an average temperature of 16°C (61°F). The month sees relatively low precipitation at 23 mm (0.9 in) over just 3 days and a humidity level of 62%. In contrast, May experiences slightly cooler temperatures, with a minimum of 0°C (32°F), an average of 14°C (58°F), and a maximum of 31°C (87°F). Although precipitation is similar at 22 mm (0.9 in), it falls over a greater number of days (5), leading to higher humidity at 81%. For more insights into weather specifics during this time, visit Chelan weather in May.
When comparing the weather in September to June, there are some notable differences. September features a wider temperature range, with a minimum of 2°C (36°F), an average of 16°C (61°F), and a maximum reaching 35°C (96°F). In contrast, June starts slightly warmer, with minimum temperatures around 4°C (40°F) and an average of 18°C (65°F), peaking at a maximum of 43°C (109°F). June also experiences higher humidity at 82%, compared to September's 62%. Additionally, June sees less precipitation, with only 9 mm (0.4 in) over three days compared to September's 23 mm (0.9 in) over the same number of days. For a more in-depth look at June's weather, you can visit Chelan weather in June.
In comparing the weather of September and July, we observe notable differences in temperature and humidity. September experiences a wider temperature range, with minimums dropping to 2°C (36°F) and maximums reaching up to 35°C (96°F), along with an average of 16°C (61°F). Meanwhile, July showcases a milder minimum of 9°C (48°F) and a higher maximum of 40°C (105°F), averaging 22°C (72°F). Additionally, September sees a bit more precipitation, with 23 mm (0.9 in) over 3 days, while July has very little rainfall at just 2 mm (0.1 in) with no rainy days at all. The humidity levels also contrast, with September sitting at 62% compared to July's higher 79%. For a more detailed look at July weather, you can visit Chelan weather in July.
In comparing the weather between September and August, September experiences a wider range of temperatures, with a minimum of 2°C (36°F) and a maximum of 35°C (96°F), compared to August's milder minimum of 7°C (45°F) and maximum of 38°C (100°F). While the average temperature in August is notably warmer at 22°C (71°F), September cools down to an average of 16°C (61°F). Precipitation is slightly higher in September at 23 mm (0.9 in) over three days, while August sees just 4 mm (0.2 in) over only one day. Humidity remains similar between the two months, with September at 62% and August at 63%. For more details on August weather, you can check out Chelan weather in August.
In September, temperatures range from a mild minimum of 2°C (36°F) to a scorching maximum of 35°C (96°F), with an average of 16°C (61°F). The month sees relatively low precipitation at 23 mm (0.9 in) over just 3 days, while humidity averages 62%. In contrast, October brings significantly cooler weather, with temperatures dipping to a minimum of -7°C (19°F) and a reduced average of 8°C (47°F), while the maximum temperature reaches 26°C (79°F). Precipitation also increases, averaging 48 mm (1.9 in) over 6 days and accompanied by higher humidity levels at 83%. For more detailed insights, check out Chelan weather in October.
In September, the weather is generally warm, with minimum temperatures around 2°C (36°F) and maximums reaching up to 35°C (96°F). This month sees relatively low precipitation, with only 23 mm (0.9 in) over about 3 days, and humidity levels at a moderate 62%.
In contrast, November brings a significant drop in temperatures, with a colder average of 3°C (37°F) and nighttime lows plummeting to -9°C (16°F). Precipitation is also much higher in November, totaling 57 mm (2.2 in) across 12 days, along with increased humidity at 89%. For more detailed insights, check out Chelan weather in November.
September and December present strikingly different weather patterns. In September, temperatures range from a mild 2°C (36°F) at night to a hot 35°C (96°F) during the day, with an average of 16°C (61°F). The month sees light precipitation of only 23 mm (0.9 in) over about three days, and humidity is relatively comfortable at 62%. In contrast, December experiences much colder conditions, with minimum temperatures plummeting to -19°C (-1°F) and an average of -2°C (29°F), peaking at 14°C (58°F). Precipitation significantly increases to 70 mm (2.8 in) across 12 days, and the humidity rises to a chilly 88%. For a closer look at December weather specifics, you can visit Chelan weather in December.
As summer fades into autumn, September in Chelan offers a refreshing transition with milder temperatures compared to the scorching highs of July and August. While the maximum temperatures can still reach a warm 35°C (96°F), the average settles comfortably at 16°C (61°F), providing a pleasant reprieve. The humidity level remains around 62%, contributing to a slightly crisp atmosphere, while rainfall is minimal, with just a few days of precipitation. This month is an ideal time to enjoy the stunning landscapes and outdoor activities before the cooler fall months arrive. For a deeper dive into what to expect throughout the year, explore the detailed Chelan Climate.