By | May 4, 2015

What you’ll need:

  • A plastic (soft drink) bottle
  • Some stones or pebbles
  • Tape
  • Marker (felt pen)
  • A ruler


  1. Cut the top off the bottle.
  2. Place some stones in the bottom of the bottle. Turn the top upside down and tape it to the bottle.
  3. Use a ruler and marker pen to make a scale on the bottle.
  4. Pour water into the bottle until it reaches the bottom strip on the scale. Congratulations, you have finished your rain gauge.
  5. Put your rain gauge outside where it can collect water when it starts raining. After a rain shower has finished, check to see how far up the scale the water has risen.

What’s happening?

Rain falls into the top of the gauge and collects at the bottom, where it can be easily measured. Try comparing the amount of rain to the length of time the shower lasted, was it a short and heavy rain shower or a long and light one?

What are the properties of warm air?

If you want to get serious you can graph the rainfall over weeks or even months, this is especially interesting if the place you live experiences varying seasons where sometimes it is very dry and other times it is very wet.

Combine your results with wind speed, wind direction and air pressure for a full weather report.