Climate Overview
The climate in Rio das Ostras is warm and mild. The average annual temperature is 24°C and approximately 1027mm of precipitation falls per year. November is the wettest month, receiving around 231mm of rainfall. Rio das Ostras is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: February, April, March. The coldest months are June, July, August, when temperatures can drop to 19°C.
Temperature
Rio das Ostras has relatively stable temperatures year-round, staying within a 10°C range. The warmest month is February, when average highs reach 29°C and the mean temperature sits around 27°C. June is the coolest month, with minimum temperatures around 19°C and an average of 21°C. Daily temperature variation is modest, with an average difference of 5°C between highs and lows. The sharpest temperature change occurs between April and May, with a 3°C shift in average temperatures.
Precipitation
Rio das Ostras is a moderately rainy area, receiving approximately 1027mm of precipitation annually, which averages out to around 86mm per month. The wettest month is November, averaging 231mm of rainfall. January and December also tend to see above-average precipitation. The driest month is July, with just 19mm. That's 211mm less than November, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Rio das Ostras is relatively calm, with an average annual wind speed of 5km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is October, averaging 5km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 4km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.
Seasons
61 days until Spring
It is currently winter in Rio das Ostras, which began on June 21, 2026. Rio das Ostras is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in February at around 29°C, while the coldest stretch bottoms out in June near 19°C. Spring is next, beginning on September 23, 2026 — 61 days from now.
Spring
Temperatures range from 21 to 25°C. Rainfall is heavy, totalling around 380mm across the season with a monthly average of 127mm. Winds are generally light, averaging 5km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 23 to 29°C. Rainfall is heavy, totalling around 407mm across the season with a monthly average of 136mm. Winds are generally light, averaging 4km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 21 to 29°C. Rainfall is relatively light, with around 144mm over the season and a monthly average of 48mm. Winds are generally light, averaging 4km/h. Layered clothing works best as temperatures gradually cool — enjoy the crisp air and changing scenery.
Winter
Temperatures range from 19 to 25°C. Rainfall is relatively light, with around 96mm over the season and a monthly average of 32mm. Winds are generally light, averaging 5km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Best Time to Visit
The best time to visit Rio das Ostras is during May, June, July, August, September and October, when the weather is most comfortable for travellers. During these months, average temperatures hover around 22°C with modest rainfall averaging 50mm per month. By contrast, February can be uncomfortably hot with temperatures reaching 29°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.
Monthly Climate Data
The table below shows monthly climate averages for Rio das Ostras based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.