July brings 27°C daytime highs, 14mm of precipitation across about 2 wet days and 15.1 hours of daylight — best for beach days, swimming and reliable sunshine. The strongest run of the year is July to September. February is the quietest month: quiet and local, and still good for low-angle light and quiet and local.
Long-run climate normals for Portland. Month ratings compare months within Portland only — they are not a ranking of Portland against other destinations, and they are not a forecast for a specific year.
Last updated: · Live forecast data refreshes hourly.
| Best month | July — Beach days, Swimming, Reliable sunshine |
| Best 3-month window | July–September |
| Quietest month | February — Quiet and local |
| Driest month | August — 12mm |
| Wettest month | December — 138mm |
| Warmest / coolest | July 27°C / February 8°C |
| Seasonality | Strongly seasonal — the months feel like different places |
| Annual rainfall | 914mm over roughly 144 rain days |
February gets roughly 564% more precipitation than July — 93mm against 14mm. That difference, more than temperature, is what changes how a day here feels.
Daytime highs only move 19°C across the whole year (8–27°C), so timing matters far less here than rainfall does.
June gives you 15.5 hours of daylight against just 8.5 in December — a 7-hour difference in how much you can actually fit into a day.
August is the driest month at 12mm across roughly 2 wet days, while December peaks at 138mm.
August is almost as good as July, but usually quieter and cheaper. If your dates are flexible, it is the easier trip.
Portland changes character completely through the year — July and February are effectively two different destinations. Pick the month that matches what you want to do, not the highest-rated one.
Ratings compare months within Portland, not against destinations worldwide: five stars means the best time to be here, not that Portland beats anywhere else. Tags describe what the conditions actually suit.
| Month | Rating | High / Low | Precipitation | Wet days | Sun | Daylight | Best for |
|---|---|---|---|---|---|---|---|
| January | ★★☆☆☆ | 8°C / 3°C | 125mm | 21 | 5h | 8.9h | Low-angle light · Quiet and local |
| February | ★★☆☆☆ | 8°C / 3°C | 93mm | 16 | 3h | 10.1h | Low-angle light · Quiet and local |
| March | ★★☆☆☆ | 11°C / 5°C | 91mm | 15 | 5h | 11.7h | Spring greenery · Quiet and local |
| April | ★★★☆☆ | 15°C / 7°C | 64mm | 11 | 6h | 13.4h | Hiking · Cycling · Spring greenery |
| May | ★★★★☆ | 20°C / 11°C | 56mm | 10 | 6h | 14.8h | Hiking · Cycling · Spring greenery |
| June | ★★★★★ | 24°C / 13°C | 38mm | 6 | 7h | 15.5h | Hiking · Cycling |
| July | ★★★★★ | 27°C / 15°C | 14mm | 2 | 11h | 15.1h | Beach days · Swimming · Reliable sunshine |
| August | ★★★★★ | 27°C / 15°C | 12mm | 2 | 11h | 13.9h | Beach days · Swimming · Reliable sunshine |
| September | ★★★★★ | 24°C / 13°C | 28mm | 5 | 11h | 12.3h | Hiking · Cycling · Reliable sunshine |
| October | ★★★☆☆ | 20°C / 11°C | 72mm | 12 | 6h | 10.6h | Hiking · Cycling · Low-angle light |
| November | ★★☆☆☆ | 15°C / 7°C | 116mm | 20 | 4h | 9.2h | Autumn colour · Low-angle light · Quiet and local |
| December | ★★☆☆☆ | 11°C / 5°C | 138mm | 23 | 3h | 8.5h | Festive season · Low-angle light · Quiet and local |
| You are planning | Pick | Why |
|---|---|---|
| Sun & beach days | July | 11h daily sunshine, 27°C highs and only 2 rain days. |
| City walking & sightseeing | September | 24°C highs with 12.3h of daylight — long days without heat fatigue. |
| Photography & light | July | 11h of sun and 15.1h daylight give the widest window for golden-hour work. |
| Value & fewer crowds | June | Scores 82/100 — close to peak conditions but outside the busiest window. |
| Cooler-weather travel | April | 15°C highs and 7°C nights suit anyone who dislikes heat. |
Each month in Portland is described from long-run climate normals and then rated relative to the other eleven months in the same city. A five-star January in a cold destination means January is one of the best times to be there — not that it beats a Mediterranean summer.
| Factor | Weight | What it measures |
|---|---|---|
| Temperature | Described | Average daytime high and overnight low for the month, shown as measured rather than judged. |
| Precipitation | Described | Monthly millimetres and wet-day count, labelled as snow or rain/snow where temperatures make that the likely phase. |
| Sunshine & daylight | Described | Average daily sunshine hours and astronomical daylight length at mid-month, from the city’s latitude. |
| “Best for” tags | Derived | Applied only when the conditions genuinely support the activity — snow depth-friendly cold for skiing, 13–24°C and low rain risk for hiking, dark evenings at high latitude for aurora. A month with few strong use cases gets fewer tags rather than padded ones. |
| Star rating | Relative | Ranks the month against the other eleven months in the same city. Never a comparison between cities. |
Figures are long-run climate averages, not a forecast for a specific year. Where a month lacks sourced rainfall or humidity, the value is modelled from temperature range and rain frequency.
July is the best all-round month in Portland: 27°C highs, 14mm of precipitation and 15.1 hours of daylight, which suits beach days, swimming and reliable sunshine. The strongest three-month window is July to September.
February — 8°C highs, 93mm of precipitation over roughly 16 days and 10.1 hours of daylight. It is the cheapest and least crowded time to go, and it still works for low-angle light and quiet and local.
August is the driest month at 12mm over about 2 rain days, against 138mm in December. Across the year Portland records around 914mm.
Yes, but the months are genuinely different trips. July suits beach days, swimming and reliable sunshine, while February suits low-angle light and quiet and local. Pick the month that matches what you want to do.
Daylight ranges from 8.5 hours in December to 15.5 hours in June, calculated from the city's latitude.