What weather system is associated with thunderstorms in tropical rainforests?

Precipitation caused by atmospheric convection is also called convective rain and thermal thunderstorm. When the air near the surface layer is heated or the upper layer is strongly cooled, the lower layer air rises, and the water vapor cools and condenses, which will form convective rain. Before the arrival of convective rain, there are often strong winds, which can pull up trees with a diameter of 50 cm, accompanied by lightning and thunder, and sometimes hail.

Convective rain is mainly produced in cumulonimbus clouds, where ice crystals and water droplets exist. The vertical thickness and water vapor content of clouds are particularly large, and the airflow fluctuates strongly, reaching 20 ~ 30m/s. Clouds are charged, so cumulonimbus clouds often develop into strong convective weather and produce heavy rain. Lightning strikes, strong winds and heavy rains often occur in such thunderstorms.

Pale cumulus clouds are thin and have low water content, so rain usually falls to the ground. Cumulus seldom rains in the middle and high latitudes, but in the low latitudes, it can sometimes produce precipitation because of its rich water content and strong convection.

Convective rainfall is the most frequent in low latitudes, and the precipitation time is generally in the afternoon, especially in equatorial regions, and the precipitation time is very accurate. In the morning, the sky is clear. With the rising of the sun, the sky cumulonimbus clouds gradually formed and developed rapidly, and became thicker and thicker. In the afternoon, cumulonimbus clouds surged, the weather was sultry, the wind passed, the thunder and lightning were mixed, and the rain poured down. The precipitation continued until dusk, and it was sunny and slightly cool after the rain, but the next day, there were repeated thunderstorms. In the middle and high latitudes, convective rain mainly appears in the summer half year and is extremely rare in the winter half year.

The equatorial region is dominated by convective rain all year round. The areas with the most convective rain in China are Hainan Island and Nanling Mountain Area. In terms of seasons, summer is the most, followed by spring and autumn. As far as diurnal variation is concerned, the land (plain area) mostly appears in the afternoon to evening, and the sea area and basin area mostly appear at night. There is less convective rain on the ocean than on the mainland.