How do you read a rain gauge?

To read a rain gauge, view the rain level, note the closest marking and carefully determine the measurement. While reading the gauge is easy, mistakes can occur.

1. View the level

   Note the level of the rain by viewing the base of the meniscus. The meniscus is the curved surface of the water that forms by surface tension as water fills the measuring tube.

2. Identify the closest marking

   Note the closest marking to the base of the meniscus on the side of the gauge. There are typically 100 markings on the tube.

3. Determine the measurement

   Find the rain level measurement by noting the number that the closest marking represents. A full gauge holds one inch of rain. Therefore, each marking represents .01 inches.