Cloud in a Jar Weather Experiment

A large glass jar with a metal lid

Very hot water (not boiling — adult handles this)

Ice cubes

Hairspray

Pour an inch of very hot water into the jar and swirl to warm the walls.

Invert the lid on top and pile ice cubes on it.

Wait 30 seconds for temperature differential to build.

Quickly lift the lid, spray a burst of hairspray in, and replace the lid.

Watch a cloud form inside the jar. It's visible, swirling, and real.

After a minute, remove the lid and watch the cloud rise out.

Try to touch it as it escapes — the cool, moist sensation is unmistakable.

This is exactly how real clouds form: warm moist air rises, meets cold air, and water vapor condenses around particles (the hairspray acts like natural dust particles).

Without the hairspray, no cloud forms. The particles are essential nucleation sites. This is real atmospheric science.

Use a dark background behind the jar to see the cloud more clearly.

Ask: "Where else do you see clouds form?" Breath on a cold day, steam from a shower, fog over a lake.

The moment the cloud escapes the jar and you can feel it on your skin is genuinely magical.