Last updated: February 24, 2025
In September, Birch Bay, United States, experiences a pleasant blend of warm and cooler weather, with maximum temperatures reaching 33°C (91°F) and an average of 16°C (61°F). The minimum temperatures can drop to 7°C (45°F), creating a diverse climate throughout the month. Rain is quite common, with total precipitation amounting to 149 mm (5.9 in) over approximately 12 days, contributing to a humidity level of 76%. This combination of warmth and occasional rainfall makes September a unique time to explore the natural beauty of Birch Bay.
In September, Birch Bay experiences a gentle transition from the summer heat as temperatures begin to cool. The minimum temperature settles around 7°C (45°F), providing a crispness in the air, while the average hovers at a comfortable 16°C (61°F), making it an ideal time for outdoor activities. The maximum temperatures still reach up to a warm 33°C (91°F), reflecting the lingering warmth of summer. This month stands out as a bridge between the high heat of August and the cooler days of October, showcasing a delightful balance of warmth and freshness that invites locals and visitors to enjoy the scenic beauty of the area.
In September, Birch Bay experiences a noticeable uptick in precipitation, with 149 mm (5.9 in) of rain over 12 days. This marks a return to wetter conditions after the typically dry summer months, where July and August recorded their lowest totals of the year at just 28 mm (1.1 in) and 23 mm (0.9 in), respectively. As fall approaches, the trend shifts significantly with precipitation levels rising sharply, foreshadowing both a drop in temperatures and an increase in rainfall that continues into October and November. This seasonal transition reflects a broader pattern where September acts as a bridge between dry summer days and the more saturated months of late fall, setting the stage for the wetter winter ahead.
September in Birch Bay marks the transition to drier conditions as humidity dips to 76%, the lowest level of the year. This decline from August’s 77% indicates a gradual shift as summer gives way to autumn. Throughout the year, Birch Bay experiences consistently high humidity, peaking in the colder months of January and February at 86%. As we move into the fall, humidity levels will rise again, culminating in October's notable 88%. This pattern highlights a cyclical rhythm, where September stands out as a brief respite from the otherwise moist climate that characterizes this coastal region.
As summer gives way to autumn in Birch Bay, the September UV Index drops to 6, indicating a high exposure category. This is a noticeable shift from the intense levels experienced in the peak summer months, where UV indexes soared to 9 in July and 8 in August, allowing just 15 minutes of safe sun exposure. In contrast, September offers a more forgiving 25 minutes of burn time, encouraging outdoor enthusiasts to soak in the last rays of summer without as much risk. This gradual decline in UV levels reflects a seasonal trend, reminding residents and visitors to remain cautious but also enjoy the outdoors as the landscape transitions to fall. For more details on UV trends and safety, visit Birch Bay UV Index.
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As summer begins to wane, September in Birch Bay boasts a delightful 251 hours of sunshine, marking a gentle transition from the sizzling heights of July, which enjoys a radiant 387 hours. This month stands as a sweet spot, retaining much of summer's warmth while welcoming the softer light of autumn. Although daylight begins to decrease, September still shines brighter than its fall counterparts, October and November, which respectively offer 181 and 124 hours. The gradual decline in sunshine from the summer peak hints at the shifting seasons, yet continues to wrap Birch Bay in a warm embrace, making it an inviting month for outdoor adventures and enjoying the beauty of nature before the chill sets in.
In Birch Bay, Washington, the likelihood of sunny weather sees a notable increase as summer unfolds, peaking in July at a promising 71%. However, as temperatures begin to cool in September, the chance of sun drops to 33%, signaling the onset of fall. This trend reflects a general pattern where late spring and summer months offer the best odds for sunshine, with September marking a transitional period before the gloomier months set in. While the chance of bright days decreases compared to the peak summer heat, September still holds potential for enjoyable weather, making it a perfect time for those looking to savor the late summer ambiance before the clouds roll in.
As September arrives in Birch Bay, the days begin to shorten, offering approximately 12 hours of daylight—a noticeable decline from the long, sun-filled days of summer. The transition marks a shift from June's peak of 16 hours to July and August, which provide a generous 15 and 14 hours respectively. This gradual tapering of daylight, moving from the brightness of May's 15 hours and the warmth of summer, sets the stage for the impending arrival of autumn. By October, daylight further diminishes to 10 hours, reinforcing a distinct seasonal rhythm that residents and visitors alike can feel as they embrace the cozy ambiance of fall.
As summer transitions into autumn, September in Birch Bay brings a refreshing shift in the air, with the average wind speed picking up slightly to 2.4 m/s (5 mph). After months of consistent breezy conditions throughout summer, this subtle increase hints at the changing seasons ahead. The winds are calmer compared to the earlier months of the year, peaking at 3.3 m/s (7 mph) in January, but maintain a light and pleasant presence, perfect for outdoor activities. As the month progresses, the wind will gradually strengthen, leading into the sharper gusts of October and November, with speeds reaching 3.1 m/s (7 mph) and 3.5 m/s (8 mph) respectively. The transition from sunny summer days to the cooler fall weather is marked by these gentle yet significant shifts in wind patterns, inviting residents and visitors alike to embrace the beauty of this coastal paradise.
The weather in Birch Bay 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 Birch Bay and find detailed weather information for every month.
September and January present starkly contrasting weather conditions. In September, temperatures can range from a mild 7°C (45°F) at night to a scorching 33°C (91°F) during the day, averaging around 16°C (61°F). The month sees a fair amount of rainfall, totaling 149 mm (5.9 in), with about 12 rainy days and a humidity level of 76%. In contrast, January is considerably colder, with nighttime lows plummeting to -9°C (16°F) and daytime highs only reaching 13°C (56°F), averaging a mere 4°C (40°F). It also experiences more precipitation, with 220 mm (8.6 in) over 16 days and higher humidity at 86%. For more detailed information, check out Birch Bay weather in January.
September and February present notably contrasting weather patterns. In September, temperatures typically range from a mild 7°C (45°F) at night to a warm 33°C (91°F) during the day, with an average of 16°C (61°F). The month sees around 149 mm (5.9 in) of precipitation over approximately 12 days, with a humidity level of 76%. In sharp contrast, February delivers chillier conditions, with nighttime lows plunging to -8°C (18°F) and daytime highs reaching just 13°C (55°F), averaging around 4°C (39°F). Despite slightly higher precipitation of 165 mm (6.5 in) spread over 17 days and increased humidity at 85%, February's weather remains significantly cooler than that of September. For more details on February weather, you can visit Birch Bay weather in February.
When comparing the weather in September and March, several notable differences emerge. September boasts a wider temperature range, with minimums of 7°C (45°F) and maximums reaching up to 33°C (91°F), providing an average of 16°C (61°F). In contrast, March starts off cooler, with temperatures dipping as low as -4°C (25°F) and averaging just 7°C (45°F), while maximum temperatures only reach up to 23°C (74°F). Precipitation levels are relatively high in both months, with September receiving 149 mm (5.9 in) over 12 days, whereas March experiences slightly more with 159 mm (6.3 in) over 16 days. The humidity remains elevated in both months, but March is notably more humid at 86% compared to September's 76%. For more detailed insights on March weather, check out Birch Bay weather in March.
When comparing the weather in September and April, several notable differences emerge. September typically enjoys a wider temperature range, with minimums around 7°C (45°F), averaging 16°C (61°F), and peaking at a warm 33°C (91°F). In contrast, April experiences cooler overall temperatures, ranging from a minimum of 0°C (32°F) to a maximum of 25°C (78°F), with an average of only 10°C (50°F).
Precipitation levels are relatively similar, with September receiving 149 mm (5.9 in) over 12 rainy days and April slightly less at 135 mm (5.3 in) over 15 days. Humidity is generally higher in April at 86% compared to September's 76%. This all contributes to the distinct seasonal climates of these months. For more specific weather details, you can check Birch Bay weather in April.
When comparing the weather in September and May, significant differences are evident in both temperature and precipitation. September boasts a wider temperature range, with minimums around 7°C and maximums reaching up to 33°C, resulting in a pleasant average of 16°C. In contrast, May has cooler temperatures, starting at a minimum of 4°C and peaking at 28°C, leading to a lower average of 13°C. Rainfall is more abundant in September, with 149 mm over 12 days, while May experiences lighter precipitation, totaling 73 mm over 10 days. Additionally, humidity levels are relatively high in both months, with September at 76% and May slightly higher at 81%. For a closer look at the specific conditions of May, you can refer to Birch Bay weather in May.
When comparing the weather in September and June, both months experience similar minimum and average temperatures, with lows around 7°C (45°F) and average highs of 16°C (61°F). However, June can escalate with maximum temperatures reaching up to 41°C (106°F), considerably higher than September's peak of 33°C (91°F). Precipitation is significantly lower in June, with only 60 mm (2.3 in) over about 9 days, contrasted with September's 149 mm (5.9 in) over 12 days. Humidity tends to be slightly higher in June at 83% compared to September's 76%. For a closer look at the June weather specifics, visit Birch Bay weather in June.
When comparing the weather in September and July, notable differences emerge. September experiences a wider temperature range, with minimums dipping to 7°C (45°F) while averaging 16°C (61°F) and peaking at a high of 33°C (91°F). In contrast, July starts off warmer with minimum temperatures at 10°C (51°F), an average of 18°C (66°F), and also reaches up to 33°C (91°F). Precipitation is significantly higher in September, receiving 149 mm (5.9 in) over 12 days, compared to July's 28 mm (1.1 in) across just 5 days. Additionally, September's humidity stands at 76%, slightly lower than July's higher level of 84%. For more specific details about July weather, check out Birch Bay weather in July.
In comparing the weather of September and August, September tends to be cooler with an average temperature of 16°C (61°F), while August boasts a warmer average of 19°C (66°F). August also experiences higher maximum temperatures, reaching up to 36°C (98°F), compared to September's maximum of 33°C (91°F). Additionally, September is significantly wetter, with 149 mm (5.9 in) of precipitation over 12 days, in contrast to August's much lighter rainfall of just 23 mm (0.9 in) over 4 days. Humidity levels remain fairly consistent, at 76% in September and 77% in August. For a more detailed look at the weather patterns, you can check Birch Bay weather in August.
September and October present a noticeable shift in weather patterns. In September, temperatures range from a minimum of 7°C (45°F) to a comfortable average of 16°C (61°F), with maximums reaching up to 33°C (91°F). This month experiences a total precipitation of 149 mm (5.9 in) over approximately 12 days, along with an average humidity of 76%. In contrast, October sees cooler temperatures, with a minimum of 0°C (32°F) and an average of 10°C (51°F), peaking at 21°C (71°F). Precipitation increases to 198 mm (7.8 in) over 16 days, combined with higher humidity levels at 88%. For more detailed weather insights, you can check Birch Bay weather in October.
In September, temperatures range from a mild 7°C (45°F) at night to a warm 33°C (91°F) during the day, averaging around 16°C (61°F). This month experiences about 149 mm (5.9 in) of precipitation over 12 days, with humidity levels at 76%. In contrast, November sees a significant drop in temperatures, with nighttime lows reaching -2°C (28°F) and daily highs peaking at 17°C (62°F), averaging just 7°C (45°F). Rainfall also increases dramatically, totaling 296 mm (11.7 in) over 19 days, accompanied by a higher humidity of 87%. For more details on the weather conditions, visit Birch Bay weather in November.
September weather showcases a wide range of temperatures, with minimums of 7°C (45°F) and daytime highs reaching up to 33°C (91°F). This month experiences an average temperature of around 16°C (61°F) and a total precipitation of 149 mm (5.9 in) over 12 days, alongside a humidity level of 76%. In contrast, December brings significantly colder conditions, with temperatures dropping to a minimum of -13°C (9°F) and a maximum of 13°C (55°F). The average temperature in December is just 4°C (40°F), and the month sees increased precipitation at 238 mm (9.4 in) across 19 days, accompanied by higher humidity at 87%. For more details on the specific weather characteristics of December, check out Birch Bay weather in December.
As the summer fades into autumn, September in Birch Bay showcases a striking transition in weather patterns. While temperatures can soar to highs reminiscent of summer, the average cools significantly, offering a refreshing balance. The month is notably wetter, with precipitation making its presence felt on around half the days, marking a shift from the drier summer months. The humidity also climbs, enveloping the area in a soft, lingering moisture that contrasts sharply with the crispness that accompanies the onset of fall. For a deeper understanding of what to expect throughout the year, visit Birch Bay Climate.