Month-by-month travel weather
Portland September weather
Portland, United States · September
Layers become more useful later in the month
Early September can still feel like summer—sunny and warm—while later in the month trends cooler.
As rain slowly reappears, a light rain option keeps plans comfortable.
September averages at a glance
Average low
around 11–13°C
Average high
around 23–27°C
Average precipitation
around 30–60 mm
Rainy days
about 5–9 days
What to wear in September in Portland
Actual feel will change with wind and rain, but use the suggestions below to build a comfortable layered outfit.
- • Light clothing by day + thin layer for evenings.
- • Optional sun protection on bright days.
- • Optional light rain layer.
Travel tips for visiting Portland in September
- • For late walks, a thin layer makes comfort consistent.
- • You may start to feel the ‘wet season approaching’ shift.
September weather in Portland — FAQ
Q. Does rain increase in September?
A. The bigger jump often starts in October, but September can still have rainy days.
Q. Is September a good time to visit?
A. Often yes—just plan for cooler evenings later in the month.
Explore Portland
These pages are connected so you can compare conditions and decide for yourself.