End of the drier season · Weather & things to do
Ilha Grande in September
Ilha Grande edges warmer than August, with highs of 82°F (28°C), lows of 66°F (19°C) and about 2.6 in (66 mm) of rain.
It scores 79/100 for comfort, 5th of 12, which makes it a solid shoulder-season month.
- Avg high
- 82°F (28°C)
- Avg low
- 66°F (19°C)
- Rain
- 2.6 in (66 mm)
- Humidity
- 76%
- Cloud cover
- 64%
- Daylight
- ~11 h 52 min
- Comfort score
- 79/100 · Great
What September feels like
Days are warm, averaging 82°F (28°C).
After dark, temperatures fall to about 66°F (19°C).
Humidity averages 76%, so the air feels sticky and the heat feels stronger than the thermometer says.
Some rain is likely, about 2.6 in (66 mm) in the month, so pack for a shower or two.
Plan around September
September is shoulder season: good weather, a step below the best months (June – August).
- Comfort slips from 89/100 in August to 79/100.
- September sits inside the Apr – Jun, Sep – Nov window our Rio, Ilha Grande & Paraty route recommends.
What to pack for September
- Light, breathable clotheshighs average 82°F
- Quick-dry fabrics76% average humidity
- Packable rain jacket or umbrellaabout 2.6 in of rain
- Comfortable walking shoesmost picks involve some walking
What to do in Ilha Grande in September
With conditions on your side, the picks below favor time outside.
Cachoeira da Feiticeira
Waterfall about 1.5 hours' walk from Abraão, with a pool for a cool swim.
Why now September scores 79/100 for comfort, good conditions for being outside.
Lagoa Verde
Emerald cove on the west side of the island, good for snorkeling among fish.
Why now Highs near 82°F and 2.6 in of monthly rain make this an easy outdoor pick.
Lazareto Ruins & Aqueduct
Ruins of a 19th-century quarantine station and a stone aqueduct on a short trail from Abraão.
Why now One to do outside while the weather is on your side.
Restaurante Dom Mario
Small, popular restaurant with generous seafood plates at fair prices.
Lua e Mar
Beachfront restaurant on Abraão's sand, known for moqueca and fish with green banana.
Nearby in September
- Paraty in September~35 mi · highs 87°F, 2.5 in rain · 3°C (6°F) warmer by day, about as wet
- Rio de Janeiro in September~65 mi · highs 78°F, 2.7 in rain · 2°C (4°F) cooler by day, about as wet
NASA POWER 2001–2025 monthly averages on a ~50 km grid, temperatures adjusted from the grid cell's ~438 m to Ilha Grande's ~6 m elevation (standard lapse rate). Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Ilha Grande in September: quick answers
Is September a good time to visit Ilha Grande?
It's a good shoulder-season choice, scoring 79/100 against a best of 89 in June – August. Expect highs of 82°F (28°C) and 2.6 in (66 mm) of rain. September is inside the Apr – Jun, Sep – Nov window our Rio, Ilha Grande & Paraty route recommends.
How hot is Ilha Grande in September?
Average highs are 82°F (28°C) and average lows 66°F (19°C), making it the 5th-coldest month by daytime highs.
Does it rain a lot in Ilha Grande in September?
Some: about 2.6 in (66 mm) of rain falls across September on average, the 5th-driest month of the year. The annual total is about 58.1 in (1475 mm).
What should I pack for Ilha Grande in September?
Bring light, breathable clothes (highs average 82°F), quick-dry fabrics (76% average humidity), packable rain jacket or umbrella (about 2.6 in of rain) and comfortable walking shoes (most picks involve some walking).
More on Ilha Grande
Routes in season in September
- Rio, Ilha Grande & Paraty Apr – Jun, Sep – Nov
Planning Ilha Grande in September?
Bring the crew into one shared trip: vote on dates, build the day-by-day plan, split costs and share one packing list.