I found this experiment on pinterest. Note the original post called for liquid watercolor, I tried to cheat and use a thin suncatcher paint. It did not work as well!! This went along with our weather unit. It shows how condensation builds up in the clouds and then leads to precipitation.
You will need a jar of water, shaving cream and liquid watercolor.
Add the shaving cream to the top of the water.
Then add your liquid watercolor until the clouds are full and the precipitation begins.
The kids loved this experiment and we ended up doing several jars or clouds:-)