How does a rain gauge measure rainfall?

A simple rain gauge can be made of anything that is transparent or at least translucent and can collect and hold rainwater. Its easiest if you can find something like a plastic water bottle that has the same diameter from top to bottom. It doesn't matter how wide the bottle is because you'll still be measuring the amount of rain that falls over a given area which is what rain gauges measure. However if you use a bottle that is wider at the base than at the top or vise versa this will skew your results due to more or less area at the top to capture rain. Some manufactured rain gauges make the tops wider than the base but the scales on the side account for this by using a graduated scale for measuring the inches or mm of rain.

1) Cut the top of the water bottle so that the opening is as wide as the width of the water bottle.

2) Use a ruler and permanent marker to make marks at regular intervals from the bottom of the water bottle to the top (1/4 inch intervals for example).

3) Mount your new rain gauge somewhere where it can collect rain during the next rain storm.

Homemade Rain gauge

Main Materials: Medium sized Plastic Bottle( bottle to hold rain water), Big sized Plastic Bottle ( outer casing) ,waterproof tape(secure the funnel and bottle).

Making raingauge is easy as it can be made out or recycled materials such as plastic bottles.