| The easiest way to measure rainfall is to use a clear, round or cone-shaped tube called a rain gauge, which is placed outside in an open area. When rain falls, it collects in the rain gauge's tube. The outside of the tube has marks measuring tenths of inches. To measure rainfall, compare the rain that accumulates in the gauge's tube to the marks on the scale. Be sure to empty and dry out the rain gauge tube after each reading, then put it back to prepare for the next reading.
Rain can also be measured with more complex electrical or weighing devices placed where eddies of air will not interfere with the normal fall of the raindrops. Meteorologists measure and report rainfall on an hourly basis to determine such things as the possibility of flooding and the need for watering lawns or crops. In addition to the daily, monthly, and annual totals, the depth of individual rainfalls and their intensity (amount of rain falling during a specific period of hours or minutes) and other pertinent facts are recorded. To keep track of rainfall like a meteorologist, measure the rainfall once every hour, then compare it against the last reading you took. The following table shows what each rainfall rate means.
| Rainfall Amount (per hour) |
Rainfall Description |
| Trace to 0.10" |
Light rain or drizzle |
| 0.11" to 0.30" |
Moderate Rain |
| Over .30" |
Heavy Rain |
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