Last updated: February 24, 2025
In August, Portland, Oregon experiences a delightful summer climate characterized by a maximum temperature of 28°C (82°F) and an average of 20°C (69°F), making it an ideal time for outdoor activities. The minimum temperature can dip to a mild 14°C (57°F), providing comfortable evenings. This month also sees about 75 mm (3.0 in) of precipitation over 9 days, contributing to the city’s lush greenery. With an average humidity level of 66%, the air feels pleasantly warm, inviting residents and visitors alike to explore the vibrant parks and scenic landscapes that define this charming city.
August in Portland, United States, brings a delightful warmth as summer reaches its peak, showcasing minimum temperatures averaging around 14°C (57°F), while the average hits a pleasant 20°C (69°F). With maximum daily highs often peaking at 28°C (82°F), the month invites residents and visitors alike to enjoy outdoor activities under the sun. This warm trend continues from the previous months, with temperatures gradually rising from the coolness of June and July. As the summer heat persists, the city's vibrant parks and waterways become bustling hubs of activity, making August a wonderful time to experience the best of Portland's outdoor charm.
In August, Portland experiences a noticeable dip in precipitation, with only 75 mm (3.0 in) of rain over 9 days. This marks one of the driest months of the year, continuing the trend established since early summer when June recorded 80 mm and July peaked at 123 mm. The decline in rainfall not only creates a brief respite from the typical Pacific Northwest gloom but also sets the stage for the transition into the wetter fall months ahead. As September approaches, rainfall slightly increases to 77 mm while maintaining a similar number of precipitation days, hinting at the return of the region's characteristic rainy season. This summer-to-fall shift highlights how August serves as a crucial bridge, allowing residents to enjoy drier days before the clouds gather once more.
In August, Portland experiences a noticeable shift in humidity, with levels dropping to 66%, marking a low point for the year. This decline follows a gradual trend of decreasing humidity from the previous months, peaking in January at a hefty 86% and steadily tapering off as summer progresses. After a mild reduction in July, August continues the trend of drier conditions, which are onset by the warmer temperatures of summer. Interestingly, the humidity begins to rise again in September, hinting at the upcoming transition into the wetter fall months. This seasonal ebb and flow of humidity not only defines Portland's climate but also contributes to its lush, vibrant landscapes.
In August, Portland experiences a UV Index of 8, categorizing it as very high exposure, which means you should be cautious when heading outdoors. This slight dip from July's peak of 9 reflects the transition towards late summer, yet the recommended burn time remains a brisk 15 minutes. As the months progress from the low levels in January and February to the scorching highs in summer, it’s clear that sun protection is crucial, especially during these peak UV months. This trend emphasizes the importance of being vigilant about sun safety to avoid harmful effects during outdoor activities. For detailed insights, check out the full UV Index Portland UV Index.
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August shines brightly in Portland, offering an impressive 336 hours of sunshine, making it one of the sunniest months of the year. This peak illuminates a clear trend of increasing daylight as summer progresses, beginning with 148 hours in January and steadily climbing through the spring and summer. After a slight dip in September, with 288 hours, the sun begins to retire, leading to a gradual decline in subsequent months, exemplified by 216 hours in October and even lower in the winter months. This vibrant summer energy not only enhances outdoor activities but also sets a picturesque backdrop for Portland's beautiful natural landscapes, inviting residents and visitors alike to bask in its warm glow.
When considering the likelihood of sunny weather in August in Portland, United States, it's interesting to note a general trend toward variability throughout the year. With only a 33% chance of sunshine, August sits below several neighboring months, such as September with 43% and the notable 54% chance in November. This decline from the sunnier spring months, like March with a 61% chance, reflects a shift in weather patterns as summer gives way to fall. July, surprisingly, sees an even lower chance of sunshine at 29%, suggesting that Portland’s summer may not be as bright as one might hope. Overall, August presents a somewhat limited opportunity for sunny days, inviting locals and visitors alike to cherish the moments when the sun does break through.
As summer fades in August, Portland experiences a notable shift in daylight duration, with a total of 13 hours of sunshine, a slight decrease from the peak of 15 hours in the preceding months of June and July. This decline marks a transition from the long, sun-soaked days of summer into the shorter daylight hours of early autumn. Following the upward trend from the winter solstice in December, where daylight is a mere 8 hours, each month progressively gains more light until July. As August wraps up, the city prepares for a gradual descent back into the cozy embrace of autumn, with daylight diminishing down to 12 hours in September. This yearly rhythm not only influences outdoor activities but also serves as a reminder of nature's cyclical patterns.
In August, Portland experiences its calmest winds of the year, with an average speed of just 3.3 m/s (7 mph), a notable dip from the breezier months before it. This trend of diminishing wind speeds begins in July and continues, contributing to the serene, sun-kissed days that characterize the late summer. As the winds ease, residents and visitors alike embrace the warmer temperatures and the vibrant outdoor scene, indulging in leisurely strolls and outdoor activities. The transition into September marks a gentle resurgence, as wind speeds start to pick up again, signaling the shift towards fall while keeping summer's relaxed spirit alive a little longer.
The weather in Portland 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 Portland and find detailed weather information for every month.
August and January present vastly different weather contrasts. In August, temperatures range from a mild 14°C (57°F) at the minimum to a warm 28°C (82°F) at the maximum, accompanied by an average of 20°C (69°F). This month sees around 75 mm (3.0 in) of precipitation over 9 days, with a humidity level of 66%. In stark contrast, January features much colder temperatures, with a minimum of -19°C (-2°F), an average of -2°C (28°F), and a maximum reaching only 12°C (54°F). Precipitation increases slightly to 97 mm (3.8 in) over the same 9-day period, coupled with higher humidity at 86%. For more specifics about January's weather, you can check Portland weather in January.
August and February present starkly contrasting weather characteristics. In August, temperatures are relatively mild, ranging from a minimum of 14°C (57°F) to a maximum of 28°C (82°F), with an average of 20°C (69°F). The month experiences moderate humidity at 66% and precipitation of about 75 mm (3.0 in) over 9 days. In contrast, February brings much colder conditions, with temperatures plummeting to a minimum of -17°C (2°F) and an average of -2°C (29°F). The maximum temperature reaches only 14°C (57°F), while humidity rises to 84%. February also sees higher precipitation levels, totaling 103 mm (4.1 in) across 10 days. For more insights into February's weather, check out Portland weather in February.
When comparing the weather in August and March, the differences are striking. August brings milder temperatures, with averages around 20°C (69°F) and maximums reaching up to 28°C (82°F), accompanied by moderate humidity at 66%. In contrast, March experiences much colder temperatures, with an average of just 1°C (34°F) and lows dropping to -15°C (6°F), alongside higher humidity at 82%. Interestingly, both months receive similar amounts of precipitation, though March has slightly more at 91 mm (3.6 in) compared to August's 75 mm (3.0 in). For a detailed look at March weather, you can visit Portland weather in March.
When comparing the weather in April and August, a stark contrast emerges. August enjoys warmer temperatures, ranging from a minimum of 14°C (57°F) to a maximum of 28°C (82°F), with an average of 20°C (69°F). In contrast, April is significantly cooler, with temperatures dropping as low as -3°C (27°F) and averaging just 6°C (43°F). While August experiences about 75 mm (3.0 in) of precipitation over 9 days, April is rainier, with 149 mm (5.9 in) across 13 days. Additionally, humidity levels are higher in April at 80%, compared to August's 66% humidity. For more details, you can check Portland weather in April.
In comparing the weather of August and May, significant differences in temperature and precipitation emerge. August typically experiences milder conditions, with average temperatures ranging from a minimum of 14°C (57°F) to a maximum of 28°C (82°F) and an average of 20°C (69°F). In contrast, May has notably cooler temperatures, with a minimum of 2°C (36°F), an average of 11°C (52°F), and a maximum of 24°C (76°F). Precipitation levels are also noteworthy; August sees 75 mm (3.0 in) over 9 days, while May records slightly higher precipitation at 94 mm (3.7 in) across 10 days. Humidity levels in August average 66%, which is lower than May’s 72%, lending a more comfortable feel to the summer month. For more detailed information, you can check Portland weather in May.
In comparing the weather in August and June, we see some notable differences. August tends to be warmer overall, with average temperatures around 20°C (69°F) compared to June's 17°C (62°F). Both months experience a maximum temperature peaking at 28°C (83°F), but June starts at a cooler minimum of 8°C (47°F), while August enjoys a milder minimum of 14°C (57°F). Precipitation is similar in both months, with June slightly wetter at 80 mm (3.2 in) versus 75 mm (3.0 in) in August, and both months report rainfall on 9 days. Additionally, humidity is relatively high in both months, though June has a slightly higher average at 72% compared to August's 66%. For more details on June weather, you can check Portland weather in June.
When comparing the weather in July and August, we observe that both months feature similar temperature ranges, with August recording slightly higher maximum temperatures at 28°C (82°F) compared to 27°C (81°F) in July. However, August experiences less precipitation, totaling 75 mm (3.0 in) over 9 days, while July has significantly higher rainfall at 123 mm (4.9 in) over 12 days. Humidity levels are relatively consistent, with July at 67% and August at 66%. Overall, August provides a slightly drier and warmer experience compared to July. For more detailed insights, check out Portland weather in July.
August and September present a notable transition in weather patterns. In August, temperatures typically range from a minimum of 14°C (57°F) to a maximum of 28°C (82°F), with an average of 20°C (69°F). The month experiences approximately 75 mm (3.0 in) of rainfall over 9 days, alongside a humidity level of 66%. In contrast, September sees a drop in temperatures, with a minimum of 8°C (46°F), an average of 17°C (63°F), and a maximum of 26°C (79°F). Rainfall is slightly higher at 77 mm (3.0 in), but it occurs over just 8 days, indicating a more concentrated precipitation pattern. Humidity also rises to 71%, making the air feel a bit heavier. For a closer look at the weather specifics in September, check out the Portland weather in September.
The weather in August is generally warmer, with temperatures ranging from a minimum of 14°C (57°F) to a maximum of 28°C (82°F) and an average of 20°C (69°F). In contrast, October experiences much cooler temperatures, with a minimum of 1°C (34°F) and an average of 12°C (54°F), peaking at 21°C (71°F). Additionally, October sees a significant increase in precipitation, totaling 163 mm (6.4 in) over 13 days, compared to August's 75 mm (3.0 in) over just 9 days. Humidity levels also rise in October, reaching 78% compared to 66% in August. For more detailed insights, you can explore Portland weather in October.
August and November present stark contrasts in weather conditions. In August, temperatures are much milder, ranging from a minimum of 14°C (57°F) to a pleasant maximum of 28°C (82°F), accompanied by moderate precipitation of 75 mm (3.0 in) over about 9 days. The humidity is relatively comfortable at 66%. Conversely, November experiences a sharp drop in temperature, with minimums plummeting to -12°C (11°F) and an average of just 5°C (42°F). Rainfall in November is more substantial, totaling 130 mm (5.1 in) spread across about 12 days, and humidity increases to 84%, adding to the overall chill of the month. For more detailed insights into November weather, you can check out Portland weather in November.
August and December present strikingly contrasting weather conditions. In August, temperatures typically range from a mild 14°C (57°F) at night to a warm 28°C (82°F) during the day, complemented by moderate humidity levels of 66% and occasional rainfall, amounting to about 75 mm over nine days. In stark contrast, December brings chilly temperatures, with lows plunging to -18°C (1°F) and daytime highs averaging just 13°C (57°F). The month also experiences increased precipitation of 144 mm across ten days and higher humidity at 81%. To learn more about December weather in Portland, you can visit Portland weather in December.
As summer peaks in August, Portland experiences warmer temperatures compared to other months, with an average of about 20°C (69°F), making it a delightful time for outdoor activities. While you can expect sunny days, there's also a chance of rain, with approximately nine days of precipitation throughout the month, adding to the region's lush scenery. Humidity tends to linger around 66%, creating a distinct atmosphere that differentiates August from the cooler, drier months of the year. Explore more about how these weather patterns shape the city by visiting Portland Climate.