Under what conditions are thermals most likely to form?

Thermals are columns of rising air that are generated by the uneven heating of the Earth’s surface. On sunny days, the ground absorbs heat from the sun, which warms the surface and, consequently, the air above it. This warm air becomes less dense than the cooler air around it and rises, creating thermals. The principle behind this is based on convection, where warm air rises and is replaced by cooler air, leading to the formation of these rising columns of air.

On cloudy days with low temperatures, there is less solar heating, which reduces the likelihood of thermals forming. Similarly, during rainstorms, the presence of precipitation and increased humidity can lead to unstable conditions, but these are often not conducive to the strong solar heating required for robust thermal development. High wind conditions can also disrupt the formation and organization of thermals, as strong winds can mix air layers and prevent the localized heating that causes thermals to develop. Thus, sunny days with significant ground heating provide the ideal conditions for thermals to form.