Rio de Janeiro · September
Run in the morning.
Comfortable average high of 80°F, dipping to 67°F at night. Humidity averages 79% — the limiting factor on most runs. Humidity rises with the sun — morning runs catch the driest, coolest window.
Avg high / low
80° / 67°F
Humidity
79%
Rain days
13/mo
Wind
10 mph
What September feels like in Rio de Janeiro
Sunrise
05:48
Mid-month average
Sunset
17:46
Mid-month average
Time-of-day breakdown
Morning
Coolest, driest air of the day. The window before sunrise is the most reliable comfortable hour.
Midday
Mild but UV and traffic peak. Workable if you don't mind shifting your pace.
Evening
Warm and runnable. Crowded routes but the air's typically calm.
What to wear running in Rio de Janeiro in September
The kit for September in Rio de Janeiro: shorts and a short-sleeve are the standard kit, a water-resistant cap or jacket on standby.
September vs the surrounding months
vs August
+2° avg high
+1 rain days
Rio de Janeiro in August →
September
80°F avg high
13 rain days
Best: morning
vs October
-1° avg high
-5 rain days
Rio de Janeiro in October →
Frequently Asked Questions
What is the best time of day to run in Rio de Janeiro in September?+
Morning. Humidity rises with the sun — morning runs catch the driest, coolest window.
What's the average temperature in Rio de Janeiro in September?+
Average high 80°F, average low 67°F.
How does September compare to surrounding months in Rio de Janeiro?+
Compared to August (avg high 77°F), September is warmer. Compared to October (avg high 81°F), September is cooler.
Does it rain often in Rio de Janeiro in September?+
Expect about 13 measurable rain days in September, on average.