Clouds form when moist air rises in the atmosphere and cools. When the water cools and condenses, it forms water vapor and clouds. Different temperature conditions create different types of clouds. Clouds move with the wind. Fast-moving clouds can move at up to 100 miles per hour although clouds in thunderstorms often travel at only 30 or 40 miles per hour.
There are four basic types of clouds. Stratus clouds appear as a low blanket of clouds across the sky. They are made entirely of water droplets, unlike cumulus clouds which can contain some ice droplets in colder climates. Cumulus clouds have a base below 7,000 feet and they are white and puffy. Cumulus clouds can form by themselves or be grouped together in clusters. Cirrus clouds form above 18,000 feet and are made mostly of ice crystals. Cirrus clouds are thin and wispy and they typically occur when the weather is calm. Cumulonimbus clouds are the tallest of all clouds and they are storm clouds. They can be as high as 60,000 feet and they produce lightning, thunder and strong winds.
To make a cloud in a bottle, put enough cool water into a large-mouthed glass jar to just cover the bottom of the jar. Hang a heavy rubber glove into the jar with the fingers pointing down and the cuff of the glove around the edge of the jar. Remove the glove, drop a lit match into the jar, and replace the cuff of the glove to seal the jar closed. Put your hand into the glove and pull the glove out of the jar without breaking the seal. Watch the fog form and then dissipate when you push the glove back into the jar.
To make a more dramatic cloud you can use rubbing alcohol. If you do this wear safety glasses to protect your eyes. Place 4 or 5 drops of rubbing alcohol into a 1 liter plastic bottle and roll it around so that the rubbing alcohol coats the bottom and sides of the bottle. Put a rubber stopper into the bottle and push the hose of a foot pump into the hole in the stopper. Pump the foot pump 15 to 20 times without letting the stopper pop out of the bottle. Pull the stopper out of the bottle and watch the cloud form.