- Clothing
- Waterproof jacket and umbrella strongly recommended.
Tomorrow's Weather Forecast - Portland
Tomorrow's weather in Portland. high 17°C (63°F), low 12°C (54°F). Rainy.
Tomorrow’s Outlook
Tomorrow will be 3°C cooler than today. Expect heavy rain in the evening, with rain chances climbing as high as 85%. That risk lines up with humidity averaging 80% through the day the more moisture in the air, the more readily clouds build into showers. Humidity holds around 80%, giving the air a damp, heavy feel even without much heat behind it. Winds stay light and calm, rarely topping 9 km/h. Sunrise is at 6:45 AM and sunset at 7:27 PM, for about 12h 41m of daylight.
- Tomorrow
- 17°/ 12°
- Today20° / 11°
Tomorrow’s Hourly Weather Outlook
Morning6 AM – Noon14°
- Rain probability
- 1%
- Wind speed
- 9 km/h
AfternoonNoon – 6 PM16°
- Rain probability
- 34%
- Wind speed
- 9 km/h
Evening6 PM – Midn15°
- Rain probability
- 85%
- Wind speed
- 8 km/h
NightMidn – 6 AM13°
- Rain probability
- 1%
- Wind speed
- 8 km/h
24-Hour Rain & Temperature Forecast
Tomorrow12 Sep
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Planning Advice for Tomorrow
- Outdoor
- Not ideal for outdoor plans or car washes — heavy rain expected.
- Travel
- Expect traffic slowdowns from wet roads. Allow extra time.
Sunrise & Sunset
Sunrise
Dawn 6:15 AMTotal Daylight
Full day forecastSolar noon 1:06 PM
Sunset
Dusk 7:57 PMvs today-4 min daylight
Sunrise shift1 min later
Sunset shift2 min earlier
5-Day Weather Forecast
Full 15-Day ForecastWeather Insight
Portland is forecast to reach a high of 17°C tomorrow, with an overnight low around 12°C. That's 8° below the long-term average high of 25°C for this time of year. It continues a recent pattern — 3 of the last 19 days with published data have run cooler than normal. Expect a high chance of rain (85% probability) and a gentle breeze averaging 9 km/h. Air quality is currently Moderate (AQI 53), driven mainly by PM2.5 at 9.2 μg/m³.
Today vs Normal
20°C-5° below normal
The long-term average high for today is 25°C.
3 of the last 19 days with published data ran above normal.
It continues that pattern - today's forecast is also running below normal.
Red = above normal, blue = at or below · last 12 days
Air Quality
Air Quality
Moderate
Air quality is acceptable for most people. Unusually sensitive individuals should consider reducing prolonged or heavy outdoor exertion.