MAKE A THUNDERSTORM
Fill the plastic container two-thirds full with lukewarm water
Let the water sit for one minute.
Place a blue ice cube at one end of the plastic container.
Add three drops of red food coloring to the water at the other end of the plastic container.
Watch what happens.
The blue and cold water sinks while the red and warm water rises. This happens because of convection. The blue water represents the cold air mass and the red water represents the warm, unstable air mass. A thunderstorm is caused by unstable air and convection plays an important part. A body of warm air is forced to rise by an approaching cold front therefore thunderstorms form.