Last updated: February 24, 2025
In August, Portland experiences a vibrant mix of temperatures, with highs soaring up to 40°C (104°F) and a pleasant average of 21°C (70°F), while the nights bring a refreshing drop to a minimum of 9°C (48°F). This month also sees relatively low precipitation, with only 8 mm (0.3 in) of rain spread over 2 days. The air carries a noticeable humidity level of 74%, contributing to the lush landscape that defines this Pacific Northwest gem. Embrace the warmth and occasional drizzle as Portland basks in the height of summer!
In August, Portland basks in the warmth of summer, showcasing a minimum temperature of 9°C (48°F) and a comfortable average of 21°C (70°F), perfect for outdoor activities and festivals. With maximum temperatures soaring to 40°C (104°F), it's not unusual for residents and visitors alike to seek relief in the city's lush parks or along the refreshing riverbanks. The month acts as a fitting climax to the season, contrasting sharply with the chill of winter months like January, where temperatures can dip to -14°C (7°F). Overall, August emerges as a vibrant time in Portland, embodying a noticeable shift into warm weather, thus enhancing the city's lively, outdoor-centric culture.
In Portland, August marks the tail end of the dry summer season, with precipitation levels dropping to a modest 8 mm (0.3 in), compared to the heavier rainfall that characterizes the earlier and later months. This slight uptick from July's virtually dry climate, which only saw 6 mm (0.2 in) of rain over a solitary day, signals the transition towards fall. With just two days of precipitation in August, the city experiences a brief respite from rain, allowing residents to revel in the sun-soaked days before the wetter months arrive. As September approaches, a marked increase in precipitation resumes, hinting at Portland's characteristic rainy season. Overall, August serves as a delicate balance between summer's brightness and the impending return of the rejuvenating rains, perfectly encapsulating the city's diverse climatic rhythm.
In August, Portland experiences a significant drop in humidity, with levels falling to 74%. This marks the lowest point of the year, as the summer heat gives way to drier air after months of consistently high humidity, peaking at 85% in the winter months of January and March. The transition into fall brings a further decline, with September seeing humidity levels drop to 71%, suggesting a gradual shift in the climate. Overall, August serves as a pivotal month, indicating the tail-end of summer's warmth and a welcoming breeze, as the city prepares for the much damper and cooler autumn months ahead.
In August, Portland experiences a very high UV Index of 8, indicating a heightened need for sun protection as the burn time is a mere 15 minutes. This trend of increasing UV exposure peaks in the summer months, with both June and July recording an even higher UV Index of 10. As the season transitions into fall, we see a slight decline, with the index dropping to 7 in September. Overall, the data highlights a significant rise in UV intensity from spring to summer, emphasizing the importance of protective measures during these warmer months. For more details on UV exposure throughout the year, visit Portland UV Index.
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In August, Portland basks in a generous 335 hours of sunshine, marking a delightful peak in the summer season. This vibrant month follows a crescendo of sunshine that begins with a modest 88 hours in January, gradually increasing each month until reaching its zenith in July with 374 hours. As the summer winds down, August still offers a robust amount of sunlight, enabling locals and visitors alike to relish the outdoors before the cooler months set in. The gradual decline in sunshine hours begins in September, dropping to 268 hours, yet the warm remnants of summer linger, creating a perfect backdrop for late-season adventures. Overall, this trend highlights how Portland's summer months are a precious time of warmth and light, inviting everyone to soak up the sun before autumn's arrival.
In Portland, August brings a notable shift in sunny weather, with a 57% chance of sunshine that stands out against the city's typically overcast months. This peak in sunny opportunities follows July's impressive 74%, yet drops to a more moderate level as summer gives way to fall. The summer months generally showcase a trend toward increased sunlight, as seen from the gradual rise from January's mere 16% to June's 63%. Post-August, the chance of sunny days begins to decline, reflecting the city's transition into the cloudier months of September and October. Therefore, while Portland’s August may not hold the title of its sunniest month, it certainly offers a delightful blend of warmth and light before the autumn days arrive.
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 an average wind speed of 2.2 m/s (5 mph), which is consistent with the lighter winds seen throughout the summer months. This gentle breeze, reminiscent of the preceding months, contributes to the city’s warm and inviting atmosphere. Observing the trends from January through August, we see a slight dip in wind speed during this peak of summer, with values hovering around 2.2 to 2.4 m/s from June to August. As autumn approaches, wind speeds gradually begin to increase, hinting at the changing seasons ahead. Overall, August offers a tranquil wind experience, making it perfect for outdoor activities amidst Portland's picturesque backdrop.
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 stark contrasts in weather conditions. August boasts a much warmer climate with temperatures ranging from a mild 9°C (48°F) to a scorching maximum of 40°C (104°F), accompanied by low precipitation of only 8 mm (0.3 in) over just 2 days and a humidity level of 74%. In contrast, January is characterized by cold temperatures, with a minimum of -14°C (7°F) and a maximum of 15°C (59°F). This month sees significantly higher precipitation at 163 mm (6.4 in) spread across 17 days and a higher humidity level of 85%. For more detailed insights, you can check Portland weather in January.
August and February exhibit strikingly different weather patterns. In August, temperatures range from a minimum of 9°C (48°F) to a scorching maximum of 40°C (104°F), with an average temperature around 21°C (70°F). The month is relatively dry, receiving only 8 mm (0.3 in) of precipitation over just 2 days, and humidity levels sit at 74%. In stark contrast, February brings much cooler temperatures, with a minimum of -7°C (19°F) and a maximum of 17°C (63°F), averaging only 5°C (41°F). This month is much wetter, accumulating 172 mm (6.8 in) of precipitation over 19 days, along with higher humidity at 84%. For a detailed look at Portland's February weather, you can check this link: Portland weather in February.
When comparing the weather in August and March, significant differences emerge. August typically boasts warmer temperatures, with daily averages around 21°C (70°F) and highs reaching up to 40°C (104°F), while March experiences cooler conditions, averaging around 8°C (46°F) and maxing out at 24°C (75°F). In terms of precipitation, August is relatively dry with only 8 mm (0.3 in) over just 2 days, whereas March sees substantial rainfall totaling 135 mm (5.3 in) spread over 17 days. Additionally, humidity levels are higher in March at 85%, compared to August's 74%. For those interested in a deeper dive into March weather specifically, check out Portland weather in March.
August and April present contrasting weather patterns. In August, temperatures range from a mild 21°C (70°F) to a scorching 40°C (104°F), with only 8 mm (0.3 in) of precipitation over just two days, resulting in a fairly dry atmosphere with 74% humidity. In sharp contrast, April experiences cooler temperatures, with a minimum of -1°C (31°F) and an average of 11°C (51°F), peaking at 29°C (84°F). This month is significantly wetter, receiving 117 mm (4.6 in) of rain across 15 days, along with higher humidity at 83%. For a detailed look at April's weather, you can visit Portland weather in April.
August and May exhibit distinctly different weather patterns. In August, temperatures can be quite high, ranging from a minimum of 9°C (48°F) to a maximum of 40°C (104°F), averaging around 21°C (70°F). The month sees only about 8 mm (0.3 in) of precipitation over just 2 days, contributing to a relatively lower humidity level of 74%. In contrast, May experiences milder temperatures, with a minimum of 2°C (36°F) and a maximum of 32°C (90°F), averaging 14°C (58°F). This month is notably wetter, with 58 mm (2.3 in) of rain spread over 10 days and a higher humidity of 83%. For a more detailed look at the conditions in May, you can visit Portland weather in May.
When comparing the weather in August and June, we see notable differences in temperature and precipitation levels. August typically boasts warmer temperatures, with a minimum of 9°C (48°F) and an average of 21°C (70°F), peaking at a high of 40°C (104°F). In contrast, June's temperatures start slightly cooler, with a minimum of 6°C (43°F) and an average of 18°C (64°F), though it can reach an astonishing maximum of 47°C (118°F).
Precipitation also varies significantly, with August receiving only 8 mm (0.3 in) over just 2 days, while June sees much more rain—46 mm (1.8 in) spread across 8 days. Furthermore, August tends to be more humid at 74%, compared to June’s higher 83% humidity levels. For a more detailed look at what to expect, you can check out Portland weather in June.
When comparing the weather in August to that of July, we notice some distinct differences. August tends to be slightly warmer, with average temperatures reaching 21°C (70°F) and maximums peaking at 40°C (104°F), compared to July's average of 21°C (69°F) and a maximum of 37°C (99°F). While both months experience mild minimum temperatures around 9°C (48°F), August sees a slight decrease in precipitation, receiving only 8 mm (0.3 in) over 2 days, whereas July reports 6 mm (0.2 in) over just 1 day. Additionally, humidity levels drop from 82% in July to 74% in August, contributing to a more comfortable atmosphere as summer progresses. For a more detailed look at July's weather, you can visit Portland weather in July.
August and September present a notable transition in weather patterns. In August, temperatures range significantly, with a minimum of 9°C (48°F) and soaring up to a maximum of 40°C (104°F), reflecting the height of summer. The month experiences relatively low precipitation, only 8 mm (0.3 in) over just 2 days, and maintains high humidity levels at 74%. In contrast, September ushers in cooler temperatures, with a minimum of 6°C (42°F) and a maximum of 35°C (95°F), resulting in an average temperature of 18°C (64°F). This month is characterized by increased precipitation, totaling 62 mm (2.4 in) over 8 days, and a slight decrease in humidity at 71%. For more detailed insights on the climate, check out Portland weather in September.
August and October present stark contrasts in weather. In August, temperatures typically range from a pleasant 9°C (48°F) at night to a scorching maximum of 40°C (104°F) during the day, with an average temperature of 21°C (70°F). Precipitation is minimal, with only 8 mm (0.3 in) recorded over just 2 days and humidity averaging 74%. In contrast, October brings much cooler weather, with temperatures dropping to a minimum of -2°C (29°F) and topping out at 26°C (79°F), averaging around 12°C (53°F). This month is significantly wetter, with 105 mm (4.1 in) of precipitation occurring over 12 days, along with increased humidity at 81%. For more specific details, you can check Portland weather in October.
August and November present stark contrasts in weather patterns. August boasts a warm climate with minimum temperatures around 9°C (48°F) and maximum highs reaching up to 40°C (104°F), averaging a pleasant 21°C (70°F). On the other hand, November experiences a significant drop in temperatures, with minimums plummeting to -5°C (24°F) and an average of only 8°C (47°F). While August sees minimal precipitation of 8 mm over just 2 days, November is characterized by much wetter conditions, receiving 155 mm of rain over 18 days. Additionally, humidity levels are higher in November at 87% compared to August's 74%. For more details on November weather patterns, you can check Portland weather in November.
The weather in August contrasts significantly with that of December. In August, temperatures fluctuate from a cool 9°C (48°F) at night to a scorching 40°C (104°F) during the day, with an average of 21°C (70°F). Precipitation is minimal, spanning only 8 mm across just two days, and humidity levels are moderately high at 74%. In stark contrast, December experiences much colder temperatures, with a minimum of -5°C (24°F) and a maximum of 16°C (60°F), resulting in an average temperature of 5°C (41°F). This month sees much higher rainfall, totaling 183 mm over 19 days, and humidity increases to 87%. For more details about winter weather patterns, check out Portland weather in December.
As summer reaches its peak, August in Portland offers a delightful contrast to the cooler months, boasting warm temperatures that often soar to a maximum of 40°C (104°F), yet average a comfortable 21°C (70°F). The weather is generally dry, with only a couple of precipitation days and minimal rainfall, making it ideal for outdoor adventures. The humidity lingers around 74%, providing a touch of moisture while still allowing for pleasant summer days. This month truly showcases the warmth of the season, inviting residents and visitors alike to enjoy everything the city has to offer. For a deeper understanding of Portland's weather patterns throughout the year, visit Portland Climate.