Last updated: February 24, 2025
In September, Coulee Dam experiences a vibrant and dynamic weather pattern characterized by a maximum temperature of 35°C (95°F), an average of 17°C (62°F), and a minimum of 2°C (36°F). During this month, the area receives a total precipitation of 24 mm (1.0 in) spread over just 3 days, resulting in a shift in the typically dry conditions. The humidity level hovers around 60%, adding a touch of muggy warmth to the pleasantly varied climate. As summer transitions to autumn, Coulee Dam presents an engaging tapestry of weather, inviting both exploration and appreciation of its natural beauty.
As summer transitions to fall, September in Coulee Dam presents a refreshing change with temperatures that distinctly reflect the changing season. The month starts off with mild mornings, averaging around 2°C (36°F), and gradually warms up to a comfortable daytime high of 35°C (95°F). This temperature range showcases a slight dip from the peak summer heat, yet still allows for plenty of warm days. The average temperature of 17°C (62°F) strikes a perfect balance, inviting outdoor activities while hinting at the cooler days to come in October. Overall, September offers a delightful mix of warmth and crispness, making it an ideal time to enjoy the stunning landscapes of Coulee Dam.
In September, Coulee Dam experiences a noticeable uptick in precipitation, measuring 24 mm (1.0 in) over three days of rain. This marks a shift from the summer's dryness, where July and August saw only minimal rainfall, accumulating just 4 mm and 8 mm respectively. As autumn approaches, the increase in moisture hints at the transition into a wetter season, with October typically bringing even more rain at 42 mm (1.7 in). September's precipitation serves as a gentle reminder that the parched days of summer are giving way to the invigorating, cooler months ahead, setting the stage for autumn's lush revival.
In September, Coulee Dam experiences a noticeable shift in humidity, dropping to an average of 60%—the lowest point of the year. This decline follows a consistent downward trend through the summer months, where humidity peaked at 62% in August. As autumn begins to set in, the transition is marked by a refreshing decrease in moisture levels, contrasting sharply with the higher humidity typical of earlier months. The environment becomes crisper, making September a particularly pleasant time to enjoy the natural beauty of the region before the winter months bring increased humidity once again, peaking at 87% in November. This rhythmic fluctuation reflects the unique climate patterns that define Coulee Dam throughout the year.
In September, Coulee Dam experiences a UV Index of 7, signaling a high exposure category that calls for caution. This marks a slight decrease from August’s peak of 9, which consistently demands vigilance due to its very high risk of harm. The burn time in September increases to 25 minutes, allowing for a bit more time outdoors compared to the intense summer months. Observing trends throughout the year, we can see a noticeable rise from the lower UV levels in the winter months, with January starting at just 2. As summer fades, the UV Index transitions from the extremes back to moderate levels by October, reminding us to stay aware of our sun exposure as we move into fall. For more detailed information, visit the Coulee Dam UV Index.
UV Risk Categories
September in Coulee Dam, United States, radiates a warm farewell to summer, basking in 291 hours of sunshine. This month marks a noticeable transition as the days begin to shorten, yet September still enjoys a lively abundance of sunlight—more than any month from October to December. The summer peak in July, with 418 hours, gently tapers off, yet September retains a vibrant glow compared to the earlier months of the year. As fall approaches, the sunshine begins to dwindle, setting a colorful stage for the upcoming autumn months. This fluctuation in sunlight beautifully illustrates nature's rhythm, where each season brings its unique charm and brightness to Coulee Dam.
As summer transitions to fall, Coulee Dam experiences a notable shift in sunny weather probabilities. September boasts a respectable 54% chance of sunshine, reflecting a decrease from the peak summer months of July and August, which enjoy sunny days 88% and 63% of the time, respectively. This slight dip indicates the onset of cooler weather; however, September still offers a healthy share of bright days compared to the cloudier months that follow. The trend of increasing sunlight through spring and summer peaks beautifully in August, before gradually giving way to the muted skies of autumn—a reminder for visitors to seize the sunny moments during this transitional month.
As summer transitions into fall, September in Coulee Dam, United States, experiences a notable shift in daylight duration, offering about 12 hours of sunlight. This marks a decrease from the lengthy 15 hours enjoyed during the peak summer months of June and July, while still providing a comfortable amount of daylight compared to the shorter days of October ahead, which will see only 10 hours. The warming glow of late summer gives way to the crisp beginnings of autumn, signaling the gradual retreat of daylight that will continue into the colder months. This rhythm of changing light mirrors the vibrant shift in the landscape, as bright greens give way to warm autumn hues, inviting both locals and visitors to revel in the beauty of the season.
As September unfolds in Coulee Dam, the average wind speed gently settles at 2.3 m/s (5 mph), reflecting a slight decrease from the summer months. Throughout the year, the winds here exhibit a subtle ebb and flow; early spring and summer months peak around 2.9 m/s (6 mph) while the autumn months present a more tranquil atmosphere as the winds soften. This transitional period is characterized by a charming balance between lingering warmth and the crispness of approaching fall, making September a serene time to experience the natural beauty of the area. The overall trend indicates steady winds throughout the year, with only minor fluctuations, creating a consistent backdrop for outdoor adventures in this picturesque region.
The weather in Coulee Dam 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 Coulee Dam and find detailed weather information for every month.
September and January present striking contrasts in weather. In September, temperatures range from a mild 2°C (36°F) at night to a warm 35°C (95°F) during the day, with an average of 17°C (62°F). The month sees relatively low precipitation at 24 mm (1.0 in) over just three days, coupled with a comfortable humidity of 60%. In stark contrast, January experiences a much colder climate, with nighttime lows plunging to -24°C (-11°F) and daytime highs only reaching 9°C (49°F), resulting in an average temperature of -2°C (28°F). The winter month also brings more precipitation, totaling 67 mm (2.6 in) over 11 days, along with higher humidity levels at 85%. For a more detailed look at January weather, you can check out Coulee Dam weather in January.
September and February present stark contrasts in weather patterns. In September, the temperature ranges from a minimum of 2°C (36°F) to a maximum of 35°C (95°F), with an average of 17°C (62°F) and a relatively low precipitation of 24 mm (1.0 in) over just 3 days. The humidity is moderate at 60%, allowing for warm and pleasant days. In contrast, February features a much colder climate, with temperatures dipping as low as -15°C (4°F) and averaging -2°C (28°F), peaking at only 11°C (53°F). The month sees significantly more precipitation at 47 mm (1.9 in) spread across 9 days, coupled with higher humidity at 86%, creating a much chillier and damp environment. For a more detailed comparison, you can check the Coulee Dam weather in February.
In comparing the weather conditions of September and March, we find notable contrasts. September typically experiences a wider range of temperatures, ranging from a cool 2°C (36°F) to a warm 35°C (95°F), with an average of 17°C (62°F). In contrast, March presents a much cooler climate, with temperatures dropping from a low of -18°C (0°F) to a maximum of 18°C (65°F), averaging only 4°C (39°F). Additionally, March tends to be wetter, with a total precipitation of 46 mm (1.8 in) over about 8 days compared to September's 24 mm (1.0 in) spread over just 3 days. The humidity also climbs significantly in March, reaching 86%, compared to September's more moderate 60%. For more detailed information on March weather in this area, you can check Coulee Dam weather in March.
September and April present contrasting weather patterns. In September, temperatures range from a brisk 2°C (36°F) to a warm 35°C (95°F), with an average of 17°C (62°F). The month sees relatively low precipitation, totaling 24 mm (1.0 in) over about 3 days, and maintains a moderate humidity level of 60%. In contrast, April experiences cooler temperatures, with a minimum of -4°C (26°F) and a maximum of 26°C (78°F), and an average temperature of 9°C (48°F). Precipitation is more frequent in April, accumulating to 39 mm (1.6 in) over 7 days, coupled with higher humidity at 82%. For more detailed information on April weather specifics, refer to Coulee Dam weather in April.
In comparing the weather of September and May, we see notable differences in temperature and precipitation. September enjoys a wider range of temperatures, with a minimum of 2°C (36°F), an average of 17°C (62°F), and a maximum reaching up to 35°C (95°F). This month experiences relatively low precipitation, totaling 24 mm (1.0 in) over just three days, alongside a humidity level of 60%. In contrast, May presents cooler averages, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 31°C (89°F) and an average of 15°C (59°F). It also sees more rainfall, accumulating 37 mm (1.4 in) over approximately seven days, contributing to a higher humidity of 77%. For a closer look at May conditions specific to Coulee Dam, you can refer to Coulee Dam weather in May.
When comparing the weather in September and June, it's clear that June typically experiences warmer temperatures, with an average of 20°C (68°F) and maximums reaching up to 43°C (110°F). In contrast, September has a lower average temperature of 17°C (62°F), with peaks hitting 35°C (95°F). Precipitation patterns also differ, as September receives more rainfall (24 mm) over three days, while June has slightly less at 13 mm over four days. Additionally, humidity is higher in June at 79%, compared to September's 60%. For more detailed insights, you can check out the Coulee Dam weather in June.
In comparing the weather patterns of September and July, significant differences emerge. September experiences a broader temperature range, with minimum temperatures dropping to a chilly 2°C (36°F) and maximums soaring to 35°C (95°F), resulting in an average of 17°C (62°F). In contrast, July is consistently warmer, boasting a minimum of 11°C (51°F) and reaching a high of 41°C (107°F), leading to an average temperature of 24°C (75°F). Precipitation is relatively low in both months, but July has even less, with only 4 mm (0.1 in) over just one day, compared to September's 24 mm (1.0 in) over three days. The humidity levels are also higher in July at 77%, compared to September's 60%. For more detailed information about July weather, you can check out Coulee Dam weather in July.
In comparing the weather between August and September, we can see some notable differences. August tends to be warmer, with average temperatures reaching 23°C (74°F) and maximums soaring up to 39°C (102°F), while September cools down significantly, featuring an average temperature of 17°C (62°F) and a maximum of 35°C (95°F). Precipitation is also lower in August, with only 8 mm (0.3 in) recorded over 2 days, compared to September's 24 mm (1.0 in) over 3 days. Interestingly, humidity levels remain similar, at around 62% for both months. For more detailed information, you can check this link: Coulee Dam weather in August.
September often ushers in warm temperatures, with averages around 17°C (62°F) and a maximum reaching up to 35°C (95°F). The month typically sees minimal precipitation, around 24 mm (1.0 in) over just 3 days, resulting in a relatively comfortable humidity level of 60%. In contrast, October experiences a significant drop in temperatures, with average highs of 8°C (48°F) and nighttime lows plunging to -7°C (20°F). The month is wetter, receiving about 42 mm (1.7 in) of rain across 7 days, and the humidity rises to 80%. These changes mark a stark transition from the warmth of early autumn to the chill of late fall. For more detailed information, check out the Coulee Dam weather in October.
September and November weather show a stark contrast in temperature and precipitation patterns. In September, temperatures can vary widely, ranging from a chilly 2°C (36°F) to a warm 35°C (95°F), with an average of 17°C (62°F) and relatively low humidity at 60%. Additionally, precipitation is minimal, totaling only 24 mm (1.0 in) over 3 days. In contrast, November experiences much colder temperatures, with a minimum of -9°C (16°F) and a maximum of 16°C (60°F), averaging just 3°C (37°F). The month is considerably wetter, bringing 51 mm (2.0 in) of precipitation across 11 days and a higher humidity level of 87%. For more detailed insights on weather in this month, check Coulee Dam weather in November.
In comparing the weather of September and December, stark contrasts become evident. September experiences relatively mild temperatures, with daily averages around 17°C (62°F) and a maximum reaching up to 35°C (95°F), accompanied by low precipitation of just 24 mm (1.0 in) over three days, and a humidity level of 60%. In contrast, December brings a much harsher climate, with minimum temperatures plummeting to -19°C (-2°F) and an average of -2°C (29°F). This month sees a significant increase in precipitation, totaling 57 mm (2.2 in) over 11 days, coupled with higher humidity at 86%. For more detailed information, you can check out Coulee Dam weather in December.
As September unfolds in Coulee Dam, it ushers in a transition from the sweltering summer heat, showcasing a more moderate climate that strikes a balance between warmth and coolness. The temperatures begin to drop, offering a refreshing respite from the peaks of summer, while occasional rainfall contributes to the changing scenery. With an average humidity of 60%, the air carries a crispness that hints at the upcoming fall. This month often stands out, contrasting with the intense heat of July and August, while also being drier than the wetter months ahead. If you're curious about the broader patterns and variations throughout the year, explore more in detail at Coulee Dam Climate.