What is the main reason for the formation of thunderclouds?

Arab Weather - The main reason for the formation of thunderclouds is the rapid rise of warm, humid air to the upper layers of the atmosphere. When this air rises, it gradually cools, and the water vapor in it condenses to form water droplets or ice crystals, which leads to the formation of cumulus clouds.

If the warm air continues to rise, cumulonimbus clouds grow to great heights, which can lead to the formation of thunderclouds (or nimbocumulus clouds). This rapid growth in clouds increases the potential for strong disturbances within them, causing electrical interactions that lead to lightning and thunder, and these clouds are often accompanied by heavy rain and sometimes hail.