Why is the temperature difference between day and night large in Rio de Janeiro, Brazil?

Due to the strong solar radiation during the day, the temperature difference between day and night is large.

According to statistics, the highest temperature in August in Rio is the fourth from the bottom, and the lowest temperature is the third from the bottom. However, the winter here is still very warm. The average temperature in August in Rio is 265,438 0.8℃, the average maximum temperature is 25.5℃, and the historical extreme maximum temperature exceeds 38.9℃. The average minimum temperature is 18.9℃, and the extreme minimum temperature is 10.6℃. No matter how cold it is, it can only be described as cool. According to statistics, there was no cold weather such as frost, rain and snow in Rio in August. However, due to the strong solar radiation during the day, the temperature drops rapidly after sunset at night, and the temperature difference between day and night is obvious.