to the study, one of the important ingredients necessary to create rain is the moisture
from atmospheric humidity, plants, bodies of water or soil.It also requires an
upward motion of air from the earth's surface into cooler parts of the upper
atmosphere and a source of water vapor. Researchers found that morning soil
moisture can affect afternoon rain accumulations over the cultivated plains
during warm seasons.
"The dry soils that enhance afternoon rain are acting like conveyor belts for warm air that's being sent into the upper atmosphere," Zeng, one of the researchers, said. "Combine that upward motion with moisture and a water vapor source, and the result is afternoon rain."
Further, as the atmospheric conditions bring moisture to the region, it acts as a source of water vapor, which, when added to the upward motion of air, produces rain.