Hail

The updraft is an up and down circulation

of air within' the storm. Water

droplets get caught in this current of air

and rise to the top of the storm, where they

freeze. They keep going up and down in the

storm, while picking up more water on it's surface

and refreezing again. They continue this process until

they become too big to be supported by the updraft

and they fall to the ground. The stronger the updraft