Last updated: February 24, 2025
August in Seattle, United States, welcomes summer's warmth with maximum temperatures reaching a sweltering 33°C (93°F), while the average temperature settles comfortably at 19°C (67°F). Despite the heat, the city experiences minimal rainfall, totaling just 16 mm (0.6 in) over 5 days, allowing for plenty of sunshine. With a humidity level of 63%, the air carries a hint of moisture, creating the perfect backdrop for outdoor activities and enjoying the vibrant scenery of the Pacific Northwest. Seattle's August weather offers a delightful blend of warmth and refreshing breezes, ideal for both locals and visitors alike.
August in Seattle marks the peak of summer, with temperatures reflecting a warm and inviting microclimate. The month showcases a minimum of 10°C (51°F), ensuring pleasant evenings, while average daytime temperatures reach a comfortable 19°C (67°F). Sun-soaked afternoons can climb to a maximum of 33°C (93°F), making it the hottest month of the year. This trend of increasing warmth from the cooler spring months culminates in August as Seattleites relish the sunniest days. As the city embraces summer's peak, locals and visitors alike are drawn to outdoor activities, exploring the vibrant parks and waterfronts that define this beautiful Pacific Northwest gem.
In August, Seattle typically experiences a noticeable dip in precipitation, averaging just 16 mm (0.6 in) of rainfall over about 5 days. This trend marks a continuation of the dry spell that begins in July, where only 18 mm (0.7 in) fell in a similar timeframe. The summer months showcase a stark contrast to the winter season, where rainfall peaks at 175 mm (6.9 in) in January, highlighting the city's reputation for its wet climate. As August rolls in, the decrease in rainy days and overall precipitation sets the stage for an array of outdoor activities and basking in the sun, making it a favored time for both locals and visitors. The limited rain in August is part of a broader seasonal cycle, with precipitation levels expected to rise again in the fall, leading into the city's signature rainy months.
In August, Seattle experiences a notable shift in humidity, dropping to 63%, making it the driest month of the year. This decline comes after a gradual decrease from the peak winter levels of 86% in January and February, and through the spring and summer months. As summer progresses, humidity fluctuates downward, reaching its lowest point before rising again in the fall, as September sees a slight increase to 62%. This trend reflects Seattle's transition from its typically moist climate to a more temperate summer, creating a refreshing contrast to the otherwise soggy ambience of the Pacific Northwest. The more comfortable humidity levels in August invite residents and visitors alike to enjoy the city's vibrant outdoor activities under the warmth of the summer sun.
In August, Seattle experiences a UV Index of 8, indicating a very high exposure category with an optimal burn time of just 15 minutes. This trend reflects the peak of summer, continuing the pattern of intensifying sunlight that begins in late spring. As temperatures soar and outdoor activities increase, residents and visitors should be vigilant about sun protection, especially as the UV Index gradually declines in September. For a detailed view on UV levels throughout the year, check out Seattle UV Index.
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August in Seattle radiates with an impressive 330 hours of sunshine, making it one of the sunniest months of the year. This delightful peak in sunlight follows a remarkable upward trend that starts from the dreary depths of winter, where January sees a mere 80 hours. As the seasons transition, daylight hours steadily increase, culminating in July's highest total of 361 hours. However, August’s sun-drenched days signal a gentle decline as autumn approaches, foreshadowing the cooler months ahead. Despite this retreat, the month still boasts significantly more sunshine compared to the earlier months, especially when juxtaposed against the gray mornings of late fall and winter, making it a cherished time for outdoor enjoyment in the Emerald City.
As summer fades into August, Seattle experiences a noticeable shift in its weather patterns, marked by a 49% chance of sunny days. While this represents a decline from the sun-drenched July, which boasts a 63% likelihood of clear skies, August still holds its own compared to earlier months. The city transitions from the vibrant brightness of late spring and early summer, where sunny days progressively increase from just 30% in March to a peak in July. Although August's chances dip, they remain significantly higher than the gloomy winter months, with January and February barely reaching 16% and 17%, respectively. This trend highlights not only the summer's winning streak but also the slow return to Seattle's characteristic cloudiness as autumn approaches.
In August, Seattle experiences a delightful 14 hours of daylight, marking a gentle transition from the peak summer months of June and July, which bask in a full 15 hours of sunlight. This gradual decline captures the essence of late summer, where long, sunlit days invite residents and visitors to enjoy outdoor adventures before the days grow shorter. As August wanes, daylight begins to shrink more noticeably, paving the way for the crisp, colorful autumn of September, which will see a reduced 12 hours of sunshine. This pattern highlights Seattle's shifting seasons, where each month brings its own unique rhythm and charm, showcasing the beauty of daylight throughout the year.
In August, Seattle experiences a gentle average wind speed of 2.4 m/s (5 mph), a slight uptick compared to the slower breezes of July, which sees winds dwindling to 1.9 m/s (4 mph). This marks a notable trend where the summer months typically showcase softer winds, with August aligning closely with the breezy patterns of early spring. As the city prepares to transition into fall, the winds of September begin to pick up again, hinting at a rhythmic gusting that characterizes Seattle's climate throughout the year. Thus, while August's winds remain calm, they serve as a precursor to the increasingly lively breezes that follow.
The weather in Seattle changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of August's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Seattle and find detailed weather information for every month.
August and January present a stark contrast in weather. In August, temperatures can range from a mild 10°C (51°F) to a warm 33°C (93°F), with an average of 19°C (67°F). This month sees relatively low precipitation at 16 mm (0.6 in) over just 5 days, along with a comfortable humidity of 63%. In contrast, January experiences much colder conditions, with temperatures dipping as low as -7°C (19°F) and only reaching a maximum of 14°C (57°F), resulting in an average of 6°C (43°F). The winter month is significantly wetter, receiving 175 mm (6.9 in) of precipitation across 16 days, accompanied by higher humidity at 86%. For more detailed information on January conditions, you can check Seattle weather in January.
August and February present stark contrasts in weather conditions. August enjoys a warm climate, with temperatures ranging from a minimum of 10°C (51°F) to a maximum of 33°C (93°F), and only 16 mm (0.6 in) of precipitation spread across five days, resulting in relatively lower humidity at 63%. In contrast, February plunges into much colder temperatures, with a minimum of -10°C (14°F) and a maximum of only 14°C (58°F). This month is significantly wetter, experiencing 177 mm (7.0 in) of precipitation over 19 days and higher humidity at 86%. For more detailed insights into February weather in Seattle, check out Seattle weather in February.
August and March weather present a striking contrast. In August, temperatures range from a mild 10°C (51°F) at night to a warm maximum of 33°C (93°F), with an average of 19°C (67°F). The month sees relatively low precipitation, totaling just 16 mm (0.6 in) over about five days, alongside a moderate humidity of 63%. Conversely, March experiences much cooler temperatures, with a minimum of -1°C (31°F), an average of 7°C (46°F), and a maximum of 22°C (72°F). It is also notably wetter, accumulating 126 mm (4.9 in) of rain over 17 days and higher humidity levels at 87%. For more detailed insights, you can explore Seattle weather in March.
When comparing the weather in August and April, it becomes clear that these months feature distinct climates. August typically boasts warmer temperatures, with a minimum of 10°C (51°F), an average of 19°C (67°F), and a maximum of 33°C (93°F), accompanied by relatively low precipitation at 16 mm (0.6 in) over just five rainy days and a humidity level of 63%. In contrast, April experiences cooler weather, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 24°C (75°F) and significantly higher precipitation levels of 117 mm (4.6 in) across 14 days, along with increased humidity at 84%. For a deeper dive into the specifics of April weather, you can check out Seattle weather in April.
When comparing the weather in August and May, several key differences emerge. August boasts higher temperatures, with averages reaching 19°C (67°F) and maximums of 33°C (93°F), while May's temperatures are notably cooler, averaging at 14°C (57°F) with highs of 28°C (82°F). Precipitation also varies significantly between the two months; August typically sees only 16 mm (0.6 in) of rain over about 5 days, whereas May can experience considerably more precipitation, averaging 68 mm (2.7 in) across 12 days. Additionally, humidity levels are higher in May at 81%, compared to August's 63%. Therefore, while August offers warmer, drier conditions, May is characterized by cooler temperatures and greater humidity. For further details, you can visit Seattle weather in May.
When comparing the weather in August and June, we can observe notable differences in temperature and precipitation. August typically offers more moderate temperatures, ranging from a minimum of 10°C (51°F) to a maximum of 33°C (93°F), with an average of 19°C (67°F). In contrast, June experiences a wider temperature range, with a minimum of 8°C (46°F) and a maximum of 38°C (101°F), averaging around 17°C (62°F). Additionally, June is significantly wetter, receiving 63 mm (2.5 in) of precipitation over 9 days, compared to August's lighter rainfall of 16 mm (0.6 in) over just 5 days. Humidity levels also differ, with August averaging 63% compared to June's higher 82%. For more details, you can check Seattle weather in June.
In comparing the weather patterns of July and August, both months exhibit similar average temperatures, with August showing a slight increase in the maximum temperature at 33°C (93°F), compared to July's maximum of 32°C (91°F). The minimum temperature in August is slightly lower at 10°C (51°F) versus July's 11°C (52°F). Precipitation levels remain relatively close, with August receiving 16 mm (0.6 in) and July a bit more at 18 mm (0.7 in), both over five days. Notably, August experiences a lower humidity level at 63%, compared to July's higher humidity of 79%, making August feel relatively drier. For more details on July's weather conditions, visit Seattle weather in July.
August tends to be warmer than September, with average temperatures reaching up to 19°C (67°F) compared to September's 16°C (62°F). While August enjoys fewer days of rain, with only 16 mm (0.6 in) of precipitation across 5 days, September sees a significant increase in rainfall, totaling 100 mm (3.9 in) over 12 days. Humidity levels remain relatively similar between the two months, with August at 63% and September slightly lower at 62%. For a more detailed look at the conditions, you can check out Seattle weather in September.
August and October showcase a striking contrast in weather patterns. August typically experiences warmer temperatures, with a minimum of 10°C (51°F), an average of 19°C (67°F), and a maximum reaching 33°C (93°F). In contrast, October sees a significant drop, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 23°C (74°F) and an average of 11°C (52°F). While August is relatively dry with only 16 mm (0.6 in) of precipitation over about 5 days, October is significantly wetter, receiving 155 mm (6.1 in) of rain across 15 days. Additionally, humidity levels rise from 63% in August to 83% in October, highlighting the transition to a cooler and more moisture-heavy climate. For more details, you can check out Seattle weather in October.
August and November present two distinctly different weather patterns. In August, temperatures range from a pleasant 10°C (51°F) at night to a scorching 33°C (93°F) during the day, with relatively low precipitation of 16 mm (0.6 in) spread over just 5 days, resulting in a comfortable humidity level of 63%. Conversely, November brings a dramatic shift; temperatures drop significantly, with lows reaching -1°C (30°F) and an average of only 8°C (47°F). The month is characterized by much higher precipitation, totaling 181 mm (7.1 in) over 18 days, and increased humidity at 89%. This stark contrast highlights the transition from the warm summer months to the chill and dampness of late fall. For more details, check out Seattle weather in November.
In August, the weather tends to be much warmer, with temperatures ranging from a minimum of 10°C (51°F) to a maximum of 33°C (93°F) and an average of 19°C (67°F). Precipitation is relatively low, with only 16 mm (0.6 in) falling over about 5 days, and humidity levels hovering around 63%. In stark contrast, December brings chilly conditions, where temperatures can dip as low as -7°C (20°F) and only reach up to 14°C (58°F), averaging at 6°C (42°F). The month experiences significantly higher precipitation at 196 mm (7.7 in) across approximately 19 days and a notable increase in humidity, peaking at 88%. For more details on December weather, you can check Seattle weather in December.
In August, Seattle experiences a delightful shift in weather compared to its other months, presenting warmer temperatures that can rise to a maximum of 33°C (93°F), providing a vibrant atmosphere perfect for outdoor activities. The average temperature settles at a comfortable 19°C (67°F), while cooler nights offer a refreshing reprieve with lows around 10°C (51°F). Although precipitation is low, with only about 16 mm (0.6 in) over five days, humidity remains at a moderate 63%, making it an enjoyable time to explore the city's beautiful parks and waterfronts. For more insights into Seattle's climate variations throughout the year, explore the details at Seattle Climate.