How do they measure the amount of rainfall?
The majority of modern automated “official” rainfall gages are called tipping buckets. They have a funnel that drains into a little divided trough that is mounted on a pivot. Each side of the trough holds the volume that is equal to 1/100 of an inch thick area of the top of the funnel. So each time 1/100 of an inch of rain falls, it tips to the other side of the trough to allow the funnel to fill the other side. There is a contact that records each time the trough tips and this is what is counted electronically. The other types that are used are the standard 8 inch gage which has an tube that is 1/10 the area of the funnel and is measured by simply inserting a ruler in the tube. Since the tube is 1/10 the area of the funnel, 1/10 inch in the tube is equal to 1/100 inch of rain. An older type gage that was recognized as the standard for many years and was used at most weather offices was called a weighing gage. It was simply a funnel that drained into a bucket that sat on a weighing sca
