波特蘭 8月 天氣
波特蘭的8月:溫暖、乾爽,還有空氣清新,是絕佳的造訪時機。
更新於 2026 年 9月 · 氣候平均值取自 ERA5 再分析
波特蘭:12 個月中排第 4 · 8月全球 1413 個中第 301 · 舒適度 89/100(等級 A)
- 白天
- 28°C
- 夜間
- 16°C
- 雨天
- 1
- 日照
- 11.8 h
- 濕度
- 57%
- 白晝時間
- 14 h

8月的波特蘭旅人筆記
Nobody on this board will predict an August here, and the variable they mean is not rain but smoke. Fires in central Oregon, eastern Washington or British Columbia can send it down the Cascades and through the Gorge into the city, and whether it arrives depends entirely on which way the wind is sitting that week; the standing advice is to have a plan B. Our AQI of 34 is a thirty-year normal and cannot see a smoke week, which is exactly why the board's warning is worth more than the column. The weather otherwise is the best of the year: 28.1C over 15.8C, 7.7mm of rain across 1.4 days, 11.8 hours of sun. The record: humidity 57 percent and an 11.6 kph wind.
波特蘭的其他月份
Regulars sum up this month with a local saying rather than a forecast: if you don't like the weather, wait five minutes - a morning can start rainy and cold and end sunny and warm, sometimes needing a rain jacket, a fleece and short sleeves all within the same day. Our row backs the mild, changeable average, 20.8C over 10.3C nights, with 50.2mm of rain across 8.3 days. Regulars are consistent that genuinely settled, predictable weather doesn't really arrive until early July, so layering isn't just advice for this month specifically - it's the baseline strategy through the whole spring stretch. The record: humidity 70 percent, 10.8 hours of sun, an 11.9 kph wind and one of the cleanest air readings in this project, AQI 34.
The local joke here is a date: summer begins on the 5th of July, because it can stay cool and showery right up to the 4th and then simply stops raining until late September. Our row is the joke in numbers - 4.5mm across 1.2 days, which is as close to a dry month as this collection holds outside the deserts. July is also the warmest, 27.6C over 15C, with the occasional run at the upper thirties. Twelve degrees between day and night and only 57 percent humidity mean the evenings are genuinely cool, and 13.1 hours of sun sit inside 15.3 of daylight. The record: a dew point of 11.5C, a 12.3 kph wind and AQI 29, among the cleanest air we hold for a large city.
September is the month long-time Oregonians name as the best of the year: sunny, dry, neither too hot nor too cold, with the least rain of the year falling between July and September. It is also when people schedule outdoor weddings, for the odds. The one risk is smoke - wildfire smoke is likelier in September than in July, unpredictable when it comes, easing later in the month, and less of a problem at the coast than inland. Our row is the dry half of that picture: 46.4mm across 5.4 days. The record: 23.9C days, 13.5C nights, humidity 67 percent and 9.8 hours of sun.
Portland forum threads describe January as genuinely variable from year to year - some winters bring mostly light drizzle and intermittent showers, others bring ice and snow, and a few bring stretches of clear, sunny cold instead. Typical daytime temperatures were cited around 35-45F, and posters were clear that Portland's reputation for constant heavy rain is somewhat overstated: one poster's data from a past January counted 23 days with measurable precipitation but only 4 of those with more than half an inch, meaning most rainy days here are genuinely light. The consistent theme across threads: expect cloudy, cool and often damp conditions as the baseline, but don't rule out the occasional bright, dry cold spell.
在地圖上波特蘭的卡片裡新增你自己的筆記。
波特蘭 氣候平均值 — 8月
每月平均值取自 ERA5 再分析。AQI 為該月美國空氣品質指數的平均值。
波特蘭在8月的人潮
這個地點本身有多擠——學校假期與大型連假、編輯標記的月份,以及天氣讓它有多搶手。從不計入舒適度分數。
人多美國的Summer break、主要客源市場中有 2 個正逢學校假期(估計)
人潮高峰人多平季人少
波特蘭天氣最好的月份
依這個目的地自己全年的氣候舒適度分數排序——這和它有多擁擠是兩回事(見上方「人潮」)。
天氣尚可波特蘭天氣最好的時候落在6月、7月和9月——是分開的兩段,不是連續的一季。
天氣最好天氣尚可天氣最差
8月的波特蘭有什麼活動
每年重複的季節活動、自然奇景、休業期和假期 — 經過編輯篩選並附上來源。
- 季節
The dry months
7月5日–9月20日 · 通常乾季The rain stops after the Fourth of July and stays away until late September, which is when the Gorge waterfalls are weakest and everything else is at its best.
- 風險
Wildfire smoke
8月1日–9月20日 · 通常煙霾季Smoke from Cascade and Gorge fires settles in the Willamette valley for days at a time in late summer, usually on the hottest and otherwise clearest weeks of the year. 來源 ↗
附近正好有活動
波特蘭方圓 300 公里內——一日遊或短程移動可達,而且這個月有活動。絕不計入舒適度分數。
波特蘭在哪裡?
8月的波特蘭 — 常見問題
- 8月適合去波特蘭嗎?
- 波特蘭的8月:溫暖、乾爽,還有空氣清新,是絕佳的造訪時機。 以 SeasonMap 的舒適度分數來看,這是 波特蘭 12 個月裡的第 4 名(89/100)。
- 波特蘭在8月的天氣如何?
- 8月的波特蘭平均最高溫 28.1°C、最低溫 15.8°C,降雨約 7.7 mm,雨天約 1.4 天。
- 波特蘭在8月的空氣品質如何?
- 波特蘭在8月的美國 AQI 月平均值約為 34。
300 公里內:Bend的Cascade Lakes Highway opens大約在5月15日–11月30日,以及Seattle的Salmon at the Ballard Locks大約在6月15日–9月20日。