Rio de Janeiro in September
In September, Rio de Janeiro averages 26°C (79°F) during the day and 19°C (66°F) at night, with around 11 days of rain (87 mm total).
High seasonConditions are warm and beach-friendly. Plan for unsettled weather and bring rain gear.
September offers comfortable temperatures in Rio de Janeiro, with some rain to plan around.
How September compares to the rest of the year in Rio de Janeiro
September is in the middle of the year for warmth in Rio de Janeiro (9th of 12) and moderately rainy compared to the rest of the year (8th of 12). Daytime temperature runs 1°C below the annual average (27°C). September runs roughly the same as August (26°C) and stays flat into October.
September sunrise & sunset in Rio de Janeiro
Times shown for Rio de Janeiro local time (America/Sao_Paulo), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in Rio de Janeiro — September
Golden-hour and blue-hour windows for the 15th of September, in Rio de Janeiro's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Rio de Janeiro in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (High season) and Rio de Janeiro's popularity.
Crowds & pricing — September in Rio de Janeiro
This is a busy month in Rio de Janeiro — not the absolute peak, but tourist numbers are clearly elevated. You'll feel it at headline attractions on weekends and in the historic centre, though side streets and lesser-known sights stay manageable. Prices are above off-season but not at their summit. A good week for first-time visitors who want everything open without the worst of the crush.
Why this tier: excellent tourism weather
Sun & mosquito risk — September in Rio de Janeiro
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Sea temperature in Rio de Janeiro — September
Across the year Rio de Janeiro's sea swings from 22.5°C (August) to 27.4°C (February) — September sits at 23.6°C.
Rio de Janeiro in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 30°C / 86°F | 24°C / 75°F | 138 mm | 13 | — |
| February | 30°C / 86°F | 24°C / 75°F | 130 mm | 11 | — |
| March | 29°C / 84°F | 23°C / 73°F | 128 mm | 13 | — |
| April | 28°C / 82°F | 22°C / 72°F | 88 mm | 11 | — |
| May | 26°C / 79°F | 20°C / 68°F | 70 mm | 9 | — |
| June | 25°C / 77°F | 19°C / 66°F | 56 mm | 7 | — |
| July | 25°C / 77°F | 18°C / 64°F | 41 mm | 7 | — |
| August | 26°C / 79°F | 19°C / 66°F | 51 mm | 8 | — |
| September | 26°C / 79°F | 19°C / 66°F | 87 mm | 11 | — |
| October | 26°C / 79°F | 20°C / 68°F | 86 mm | 13 | — |
| November | 28°C / 82°F | 21°C / 70°F | 108 mm | 13 | — |
| December | 29°C / 84°F | 23°C / 73°F | 130 mm | 14 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for Rio de Janeiro in September →
Frequently asked questions
How hot is Rio de Janeiro in September?
In September, Rio de Janeiro averages a high of 26°C (79°F) and a low of 19°C (66°F) — generally warm.
Does it rain a lot in Rio de Janeiro in September?
September can be fairly wet in Rio de Janeiro, with about 11 rainy days on average.
Is September a good time to visit Rio de Janeiro?
September is warm. It suits travelers who are comfortable with warm weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Rio de Janeiro in September?
Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full September packing list for Rio de Janeiro for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.