Weather School / First Weather · ages 2 to 5

The weather rock looking surprised in a storm while a big yellow lightning bolt flashes and the numbers one, two, three float in the sky.

Counting the Thunder

How far away is that storm? You can count it.

The weather rock outside under a storm sky, waiting to be looked at.

The mission: guess first, then go look

When the sky flashes, guess: close or far? Say it fast, before the boom arrives.

From inside, a few steps back from the windows: flash, count slowly, boom. Five slow counts is about one mile of sky. Now you know something the storm did not tell you.

In a storm, the flash and the boom happen together, far away in the sky.

The light reaches your eyes almost at once. The sound takes its time.

So the longer the quiet after the flash, the farther away the storm is.

Professor Weather Rock in a graduation cap, pointing upward with a wooden pointer.

Professor Weather Rock says

Sound is a slowpoke. Thunder needs about five whole seconds to travel one mile, and light makes the same trip faster than you can blink.

Rocktivity Time!

Pick a door. Every door is a good one.

Move like the weather

Make thunder travel. Your grown-up flicks the light and claps at the very same moment: that is a close storm, flash and boom together. Now the light flicks, the grown-up waits, and then claps: that is a far storm. The farther away the storm, the longer the boom takes to reach you. That is the storm's whole trick.

Ask them

“Was that boom close or far away? What did your counting say?”

The Rocktivity

When you see a flash, count slowly until the boom. Five slow counts means the lightning was about a mile away. Count again at the next flash. Are your numbers growing or shrinking?

While the storm rains, try this

Listen to what it plays: the window taps, the roof drums, the gutter gurgles. Which is loudest? A storm is a band, and every house hands it different instruments.

Is the rock right?

You looked with your own eyes. The rock is outside looking too. Ask it what it sees, then decide together who read the sky better.

Words we learned

Countverbsay it: KOWNTTo say numbers in order: one, two, three.

Boomnounsay it: BOOMA big deep sound, like the one thunder makes.

For the grown-up

Growing counts mean the storm is leaving; shrinking counts mean it is coming. That one comparison turns a scary night into a measurement, which is the whole trade of meteorology. Indoors for all of it: when thunder roars, go indoors.

Take it off the screen

A colouring sheet with the big word to trace, plus the whole lesson in print. Free for any home or classroom.

Print the colouring sheet and lesson (PDF)

The trail continues

Next storm, count every flash and watch your numbers. Shrinking counts mean the storm is coming closer. Growing counts mean it is packing up to leave.

And that boom you keep counting? Storms and Thunder knows where it is born.