Climate Insights for Biritiba Mirim

The climate in Biritiba Mirim is warm and mild. The average annual temperature is 21°C and approximately 2305mm of precipitation falls per year. Biritiba Mirim receives a notable amount of rainfall throughout the year, including during its driest month. Biritiba Mirim 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: January, February, March. The coldest months are July, August, June, when temperatures can drop to 14°C.

Biritiba Mirim sees moderate temperature variation throughout the year, ranging from 14°C to 29°C. The warmest month is January, when average highs reach 29°C and the mean temperature sits around 25°C. July is the coolest month, with minimum temperatures around 14°C and an average of 18°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows. The sharpest temperature change occurs between April and May, with a 2°C shift in average temperatures.

Biritiba Mirim is a very wet location, receiving approximately 2305mm of precipitation annually, which averages out to around 192mm per month. The wettest month is February, averaging 372mm of rainfall. January and March also tend to see above-average precipitation. The driest month is July, with just 55mm. That's 317mm less than February, 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.

Biritiba Mirim is relatively calm, with an average annual wind speed of 10km/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 11km/h, though still comfortable for most outdoor activities. The calmest conditions occur in March, with average winds dropping to 10km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 1km/h between the calmest and windiest months.

It is currently autumn in Biritiba Mirim, which began on March 20, 2026. Biritiba Mirim 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 January at around 29°C, while the coldest stretch bottoms out in July near 14°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Biritiba Mirim is during June, July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 78mm per month. By contrast, January can be uncomfortably hot with temperatures reaching 29°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Biritiba Mirim 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.