A barometer measures air pressure. The higher the air pressure, the better the weather. The lower the pressure, the greater likelihood we’ll see active weather, perhaps severe weather.

You can make your own barometer. Here’s how.

You’ll need a glass jar, a spool and a pencil. Also, a balloon and a straw. A marked index card and tape. Finally, a needle or toothpick.

Now, cut and stretch the balloon over the top of the jar. Then glue the straw to the top of the balloon.

Attach your needle or toothpick to the other end of the straw. Next, insert the pencil in the spool and tape your index card to the pencil.

When the air pressure is lower, the balloon will expand, pushing the straw and needle down, toward the low pressure marking.

When the air pressure is high, the balloon will contract into the jar and the straw and needle will move up to the high pressure marking.