Portland Weather in August
With daytime temperatures of 28°C (82°F) and nighttime lows of 14°C (57°F), August in Portland brings high temperatures during the day. It is also the driest month of the year, with minimal rainfall.
Rainfall in Portland in August
This is the driest month, making it a great choice for planning outdoor excursions. Based on our climate data of the past 30 years, about 3 days of rain are anticipated, with 11 mm (0.4 in) on average. The occasional light shower is possible, but rain is rarely an issue this month.
Temperature in Portland in August
August is a perfect month in Portland, with 28°C (82°F) during the day and 14°C (57°F) at night. The summer season is characteristic of August. The days can feel warmer than the evenings, so packing for both parts of the day is a good idea. Nights drop to around 14°C (57°F), which is noticeably cooler than the daytime. A light jacket for the evening is a sensible addition, and the cool nights tend to make sleeping comfortable. On average, this month sees the highest temperatures of the year. Worth packing a few lighter outfits.
Sunshine in Portland in August
Expect a lot of sunshine this month, with about 298 hours of sun. These sunny conditions add to the overall experience.
Wind Speed in Portland in August
August has wind speeds averaging 3 m/s (6 knots). You can expect comfortable light winds that steadily move flags and feel mild throughout the day. Since this is an average, daily conditions vary from gentle winds to more active breezes.If you're inclined towards comfortable temperatures and drier conditions, August is a good time to visit Portland.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Portland's climate page.
Portland Temperature in August
Min Temperature
14°C (57°F)
Max Temperature
28°C (82°F)
Chance of Rain
10%
Precipitation
11 mm (0.4 in)
Rainy days
3 days
Humidity
65%
Windspeed
3 m/s (6 knots)
Sunshine
298 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Portland typically stay consistent throughout August, with daily highs averaging around 28°C (82°F). Nights are pleasant, with lows around 15°C (59°F).
Average temperatures in August
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in August
Historical weather for Portland in August
Browse day-by-day weather records for Portland spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Portland historical weather extremes in August
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Portland.
- On August 14, 2023, temperatures climbed to 41°C (106°F), marking the warmest August day on record.
- Portland experienced its chilliest August day on August 1, 1989, reaching only 16°C (61°F).
- Nighttime temperatures dropped to 7°C (45°F) on August 29, 1980, marking the coldest August night on record.
Best Places in the United States of America in August
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in August →
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What to Wear in Portland in August
Warm but pleasant conditions in Portland in August. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. Dry conditions mean you won't need to worry about rain protection. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in Portland in August
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Portland's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed
See the full Portland climate overview or explore weather in the United States of America.
