The density difference between the surrounding air and the cloud itself helps hold the cloud ring together. Since cool air is more dense, it is easier to see clouds as the warm wet air meets the cool dry air.
This activity will allow you to simulate a cloud for yourself.
Please follow safety precautions. Avoid breathing the powder. Be careful with sharp objects.
Carefully cut a dime-sized hole in the center of the bottom of the tub, making sure the edges are smooth. Open the balloon and stretch it across the top of the tub. Secure it in place with rubber bands or tape so that no air escapes around the edges. Gently shake a small amount of the powder into the tub so that it lines the inside surface of the balloon. Hold the container balloon-side downward. Pinch the center of the balloon and pull downward. Quickly release the balloon to produce a small cloud of powder coming from the hole in the container. (Sometimes a quick snap upward on the balloon produces the desired result.) Observe the direction and speed of the cloud. How is it different than the surrounding air? What gives the cloud its force?
(This activity can be done using dry ice instead of powder to produce the cloud, but it is not recommended with small children.)