March weather forecast
Rio de Janeiro, Brazil

March introduces fall in Rio de Janeiro, chaperoning milder weather compared to the scorching summer months. It's the month that sees the highest relative humidity of 81%, accompanying lower, yet still warm temperature peaks at 28.3°C (82.9°F). Coinciding with lesser daylight hours compared to the previous two months, the overall ambience becomes noticeably less intense. With a decrease in the sea temperature, those willing to brave the waves can expect a slightly cooler dip. Despite the drop in several weather metrics, March offers a more comfortable climate for outdoor ventures in Rio.

Temperature

Rio de Janeiro's weather in March displays an average high-temperature of a still warm 28.3°C (82.9°F), showing minor disparity from February's 29.7°C (85.5°F). March witnesses an average nighttime temperature of 22.9°C (73.2°F) in Rio de Janeiro.

Heat index

The heat index value for March is estimated at a tropical 33°C (91.4°F). Adopt heightened safety measures, heat cramps and heat exhaustion may occur. Sustained activity might cause heatstroke.
Heat index values are typically calculated for conditions of shade and a light breeze. An exposure to direct sunlight may lift the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. Be aware that direct exposure to sunlight increases heat impact and may raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Young individuals usually face greater risks than adults as their sweat production is less. Also, their larger skin surface relative to their small bodies and the high heat generation due to their activity contributes to their vulnerability.

Humidity

In March, the average relative humidity in Rio de Janeiro is 81%.

Rainfall

In Rio de Janeiro, Brazil, in March, it is raining for 22.7 days, with typically 85mm (3.35") of accumulated precipitation. Throughout the year, in Rio de Janeiro, there are 192.5 rainfall days, and 812mm (31.97") of precipitation is accumulated.

Sea temperature

With an average sea temperature of 25.8°C (78.4°F), March is the month with the warmest seawater in Rio de Janeiro.
Note: Water temperature between 25°C (77°F) and 29°C (84.2°F) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

Daylight

In Rio de Janeiro, Brazil, the average length of the day in March is 12h and 13min.
On the first day of the month, sunrise is at 05:48 and sunset at 18:20. On the last day of March, in Rio de Janeiro, sunrise is at 06:00 and sunset at 17:52 -03.

Sunshine

The average sunshine in March is 8.3h.

UV index

In March, the average daily maximum UV index is 6. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: In March, a regular UV index of 6 translates into these guidelines:
Avoid excessive sunlight. Those with lighter skin may experience burning in less than 20 minutes. Between 10 a.m. and 4 p.m., the Sun emits the most powerful UV radiation. Limit direct exposure to the Sun during these hours. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Notice! Sand and water reflections contribute to a stronger UV exposure.