Brazil
Rio de Janeiro in September: weather, sea & travel advice
This month's data profile
Rain shapes the decision
Rio de Janeiro in September is climatically well suited to city breaks, family holidays and beach holidays. The average daily high is around 26 °C, and the sea is about 21 °C. With about 12 rainy days it is wet.
Historical monthly averages, not a weather forecast. Individual days and years can differ substantially.
Rank among 12 monthly averages
76/100 · #5
Warmth
#8
Dryness
#5
Sun
#7
Sea warmth
#11
Published best categories: none
Rio de Janeiro · SeptemberPhoto: Jens Hausherr from Hamburg, Deutschland · CC BY-SA 2.0Climate facts
- Average high
- 26 °C
- Average low
- 19 °C
- Sea
- 21 °C
- Rainy days (est.)
- 12 rainy days (est.)
- Sun (est.)
- 6 h/day
- Humidity
- 78 %
Climate evidence with direct month comparison
The highlighted row is the selected month. Precipitation total and rainy days are separate monthly averages.
| Month | Avg high °C | Avg low °C | Rainy days (est.) | Precipitation mm | Sun h/day (est.) | Humidity % | Wind m/s | Sea °C | Score |
|---|---|---|---|---|---|---|---|---|---|
| August | 25 | 18 | 8 | 47 | 5.3 | 77 | 3.0 | 21 | 83 |
| September (selected) | 26 | 19 | 12 | 82 | 5.6 | 78 | 3.1 | 21 | 76 |
| October | 26 | 20 | 15 | 116 | 6.1 | 80 | 3.0 | 22 | 70 |
How do the previous and next months compare?
Baseline: September (76/100)
Positive and negative values show the change from the selected month.
| Score Δ | Average high Δ | Average low Δ | Rainy days Δ | Rain Δ | Sun Δ | Humidity Δ | Wind Δ | Sea Δ | |
|---|---|---|---|---|---|---|---|---|---|
| August | +7 | -0.8 °C | -0.8 °C | -3.5 | -34.7 mm | -0.3 h | -0.4 % | -0.1 m/s | -0.1 °C |
| October | -6 | +0.6 °C | +1.1 °C | +3.7 | +34.6 mm | +0.5 h | +2.2 % | -0.2 m/s | +0.4 °C |
All twelve months in context
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Useful next decisions
Frequently asked questions
How warm is Rio de Janeiro in September?
The average daily high is around 26 °C, with an average daily low of about 19 °C.
Can you swim in Rio de Janeiro in September?
The sea is about 21 °C (swimmable).
Does it rain a lot in Rio de Janeiro in September?
The curated estimate is about 12 rainy days per month, not a directly measured long-term average. Total precipitation averages around 82 mm for the month. A rainy day does not mean all-day rain.
When is the best time to visit Rio de Janeiro?
By the climate score, May, June, July and August are the strongest months for Rio de Janeiro. For a beach trip: February, April, May and June. September is not among them.