Last updated: February 24, 2025
September in Olympia, United States, ushers in a delightful transition with average temperatures around 16°C (61°F), peaking at a maximum of 31°C (88°F). While the days can be pleasantly warm, they also invite occasional cool breezes, with nighttime lows dipping to 6°C (43°F). This month witnesses about 88 mm (3.5 in) of precipitation, spread across roughly 10 days, creating a refreshed atmosphere enhanced by a 74% humidity level. Nature thrives under these conditions, making September a vibrant time to experience the beauty and charm of Olympia.
In September, Olympia enjoys a comfortable transition into autumn, with temperatures reflecting a pleasant mix of summer's warmth and autumn's coolness. The minimum temperature settles at 6°C (43°F), while the average creeps up to 16°C (61°F), offering mild days perfect for outdoor adventures. As the maximums reach a warm 31°C (88°F), residents and visitors alike can relish in the lingering warmth before winter sets in. This month signifies a shift from the peak summer warmth of August, where temperatures soared into the 30s, to a gradual cooling that heralds the beautiful fall colors ahead. The overall trend highlights a gentle decline, making September an ideal time for enjoying Olympia's natural beauty and vibrant community events.
In September, Olympia experiences a noticeable increase in precipitation with 88 mm (3.5 inches) of rain, marking a transition from the dry summer months. This uptick is reflected in the 10 rainy days, as the city prepares for the wetter autumn season ahead. Compared to the minimal rainfall of 9 mm in July and 12 mm in August, September serves as a bridge, paving the way for the more substantial rains of October, which averages 133 mm. With the onset of fall, locals can expect a shift in weather patterns, heralding the return of the lush, green landscapes characteristic of the Pacific Northwest.
As September unfolds in Olympia, United States, residents experience a modest drop in humidity, averaging around 74%. This marks a continuation of the downward trend seen through the summer, where August recorded the lowest humidity of the year at 73%. While the air feels relatively drier this time of year, it’s a stark contrast to the heights of winter, where humidity peaks at a substantial 86% in January and November. As autumn approaches, the gradual shift in humidity not only signals the onset of cooler temperatures but also offers a refreshing change from the dampness pervasive in earlier months. This seasonal transition creates an inviting atmosphere, perfect for enjoying the crispness of early fall.
As September arrives in Olympia, the UV Index settles at a moderate to high level of 7, indicating a need for sun safety precautions during outdoor activities. This marks a slight decrease from the peak summer months of August and July, when the UV Index reached 8 and 9, respectively. With a burn time of just 25 minutes, it's essential to stay vigilant, especially as the sun begins to shift lower in the sky. The trend shows that while September provides a welcome transition from the intense summer sun, skin protection remains crucial as we head into the fall. For detailed updates and information, check out Olympia UV Index.
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As summer begins to wane, September in Olympia offers a delightful blend of warmth and brightness, boasting 257 hours of sunshine. This month, while lower than the sun-drenched July and August, still shines brightly compared to the dimmer days of fall that follow. After peaking at 362 hours in July, sunshine hours gradually decline, but September provides a golden opportunity to savor the lingering warmth before autumn settles in. This trend of gradually decreasing sunlight reminds us of the seasonal transition, where the brilliance of summer gradually yields to the softer, cooler days ahead. With this inviting amount of sunshine, September invites residents and visitors alike to enjoy outdoor activities, bask in the sun’s glow, and celebrate the beauty of early autumn in the Pacific Northwest.
In September, Olympia experiences a 35% chance of sunny weather, marking a noticeable decline from the summer months while still offering a decent opportunity for sun lovers. As the summer heat peaks in July at 60%, the sunny days gradually taper off, with August bringing a still-respectable 48%. The change in weather signals the transition to fall, as the likelihood of sunshine drops to 47% in April and 34% in May before the autumn chill arrives. This trend suggests that while September may not boast the highest chances of sunny days, it still holds a place among the more favorable months for basking in the sun compared to the winter depths of January and February, where sunlight is merely a fleeting dream.
As September arrives in Olympia, daylight begins to wane, showcasing a subtle transition from the long, sun-filled days of summer to the brisk embrace of autumn. With an average of 12 hours of daylight, September marks a noticeable decline from the 15 hours enjoyed in the peak of summer. The gradual shift reflects a rhythmic cycle, where the days grow shorter leading into fall. This month serves as a gentle reminder of nature's ebb and flow, highlighting the changing seasons as we prepare for the cozy months ahead. As daylight recedes, residents can savor the remaining warmth and bright skies, making the most of these golden early autumn days.
In September, Olympia enjoys a gentle breeze with an average wind speed of 2.5 m/s (6 mph), mirroring the calmness of the preceding months. This consistency highlights a trend of relatively mild winds throughout late summer and early autumn, with only slight variations. As the seasons change, September's winds remain steady, providing a pleasant backdrop for outdoor activities. Interestingly, this month sets the stage for a gradual increase in wind speed leading into autumn, as recorded winds begin to pick up slightly in October. Overall, September captures the essence of gentle transition, perfectly balancing the lingering warmth of summer with the crispness of the approaching fall.
The weather in Olympia 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 Olympia and find detailed weather information for every month.
September and January present two starkly contrasting weather profiles. In September, temperatures range from a minimum of 6°C (43°F) to a warm maximum of 31°C (88°F), with an average temperature of 16°C (61°F). Precipitation is moderate, totaling 88 mm (3.5 in) over about 10 rainy days, with a relatively comfortable humidity level of 74%. In contrast, January sees much cooler temperatures, with a minimum of -6°C (21°F) and a maximum of only 14°C (57°F), averaging around 5°C (42°F). This month experiences significantly higher precipitation at 197 mm (7.8 in) spread over 16 days, alongside increased humidity at 86%. For a deeper look at January's weather, you can refer to Olympia weather in January.
When comparing the weather in September and February, it's clear that these months present distinct climatic conditions. September typically enjoys milder temperatures with a minimum of 6°C (43°F) and an average of 16°C (61°F), peaking at a comfortable 31°C (88°F). The humidity is relatively lower at 74%, and precipitation averages 88 mm (3.5 in) over about 10 days. In contrast, February is much colder, with temperatures dipping to a minimum of -5°C (23°F) and averaging around 5°C (41°F), with highs only reaching 14°C (58°F). This month also sees more precipitation, averaging 155 mm (6.1 in) over 17 days, and a higher humidity level of 84%. For more detailed insights on February weather, you can visit Olympia weather in February.
In September, the weather is characterized by a wider temperature range, with minimums around 6°C (43°F) and maximums reaching up to 31°C (88°F), averaging 16°C (61°F). Precipitation is moderate at 88 mm (3.5 in) over about 10 days, accompanied by a relative humidity of 74%. In contrast, March experiences cooler temperatures, starting with minimums as low as -1°C (30°F) and averaging only 7°C (45°F), with highs around 22°C (73°F). The month sees a significant increase in precipitation, totaling 134 mm (5.3 in) over 16 days, with humidity levels slightly higher at 85%. For more details, you can check Olympia weather in March.
Comparing the weather of September and April reveals notable differences in temperature and precipitation patterns. September typically enjoys milder daytime temperatures, ranging from a comfortable minimum of 6°C (43°F) to a warm maximum of 31°C (88°F), with an average of 16°C (61°F). In contrast, April begins the spring season with cooler temperatures, featuring a minimum of -1°C (31°F) and a maximum of 25°C (78°F), averaging around 10°C (50°F). When it comes to precipitation, April sees a higher amount (117 mm) over more days (14) compared to September's 88 mm over 10 days, indicating a wetter start to spring. Additionally, humidity levels are higher in April at 83%, compared to September's 74%. For more detailed information about the weather in April, you can visit Olympia weather in April.
September and May present distinct weather patterns, reflecting the transition from summer to fall. In September, temperatures can range from a cool 6°C (43°F) to a warm 31°C (88°F), with an average temperature of 16°C (61°F). The month sees about 88 mm (3.5 in) of precipitation over approximately 10 days, and humidity averages around 74%. In contrast, May tends to be slightly cooler, with temperatures ranging from 4°C (40°F) to a maximum of 29°C (85°F), and an average temperature of 13°C (56°F). May experiences less rainfall, totaling 65 mm (2.6 in) over 9 days, with a higher humidity level of 84%. For more details on weather conditions during this month, you can check Olympia weather in May.
September and June both feature similar average temperatures, hovering around 16°C (61°F). However, September experiences a wider range in daily highs, with maximum temperatures reaching up to 31°C (88°F), while June can peak dramatically at 40°C (104°F). In terms of precipitation, September sees more rainfall with 88 mm (3.5 in) over about 10 days, compared to June's 51 mm (2.0 in) across 7 days. Additionally, humidity levels are slightly higher in June at 84%, compared to September's 74%, contributing to a more humid feel during the early summer month. For more details on the weather during June, you can check Olympia weather in June.
September weather exhibits a broader temperature range compared to July, with minimum temperatures dipping to 6°C (43°F) and maximums reaching 31°C (88°F), resulting in an average of 16°C (61°F). In contrast, July temperatures remain milder, with a minimum of 10°C (49°F) and a maximum of 33°C (92°F), averaging 18°C (65°F). Additionally, September experiences significantly more precipitation, with 88 mm (3.5 in) over 10 days, whereas July is much drier, receiving only 9 mm (0.4 in) over just 2 days. Humidity levels are slightly lower in July at 82% compared to September’s 74%. For more details, check out Olympia weather in July.
In comparing the weather of September and August, September tends to be cooler overall, with average temperatures ranging from a minimum of 6°C (43°F) to a maximum of 31°C (88°F). In contrast, August experiences slightly higher temperatures, with minima at 9°C (49°F) and maxima reaching up to 34°C (93°F). Precipitation also notably differs, as September witnesses 88 mm (3.5 in) of rain over an average of 10 days, while August is relatively dry, receiving only 12 mm (0.5 in) over just 2 days. Both months exhibit similar humidity levels, around 74% in September and 73% in August, but the increased rainfall in September can make it feel more substantial. For more detailed insights, you can check Olympia weather in August.
In September, temperatures ranged from a chilly 6°C (43°F) at night to a warm 31°C (88°F) during the day, with an average of 16°C (61°F). The month saw 88 mm (3.5 in) of rain across about 10 days, with humidity levels around 74%. In contrast, October brings a noticeable drop in temperatures, with minimums reaching only 1°C (34°F) and daytime highs averaging at 24°C (75°F). Precipitation increases to 133 mm (5.3 in) spread over 12 days, and humidity rises to 83%. These changes signal a shift towards cooler, wetter conditions as autumn progresses, as detailed in Olympia weather in October.
September weather in Olympia is characterized by warm temperatures, with an average of 16°C (61°F) and a maximum reaching up to 31°C (88°F). The month sees a moderate amount of precipitation, totaling 88 mm (3.5 in) over about 10 days, along with a humidity level of 74%. In contrast, November brings a significant shift, as temperatures drop, with a minimum of -1°C (30°F), an average of 8°C (46°F), and a maximum of 17°C (62°F). Additionally, November is much rainier, with precipitation reaching 192 mm (7.5 in) across 17 days and a higher humidity of 86%. For more details on the weather in November, you can check Olympia weather in November.
In September, the weather in Olympia features a warm climate with temperatures ranging from a cool 6°C (43°F) to a high of 31°C (88°F), averaging around 16°C (61°F). The month sees some rainfall, approximately 88 mm (3.5 in) over about 10 days, accompanied by a humidity level of 74%. In contrast, December brings a much colder atmosphere, with temperatures dipping to a minimum of -5°C (23°F) and peaking at 13°C (56°F), resulting in an average temperature of 5°C (42°F). Precipitation significantly increases to 203 mm (8.0 in), occurring over 18 days, with humidity rising to 87%. For more details on the weather in December, you can visit Olympia weather in December.
As September unfolds in Olympia, the weather begins to transition from the warmth of summer, bringing a delightful mix of mild temperatures and increased precipitation. The days still hold onto the last vestiges of heat, yet there is a noticeable crispness in the air as the month progresses. This combination of warmth and moisture leads to a comfortable atmosphere, albeit with a hint of humidity that sets it apart from the drier summer months. If you're looking to explore the unique charms of Olympia's September climate, you can find more details here: Olympia Climate.