Rain Gauge – How Does It Work?


If you are no pro in the study of the weather phenomenon, then you may not fully understand what the rain gauges are or how they work to fulfill their purpose. On a professional level, these instruments are considered indispensable especially because they are used to examine and gauge the amount of precipitation at a particular point in time.

Undoubtedly, the quantity of rainfall is different from one place towards another. You cant expect that your location gets the same or an an equal amount of precipitation with the rest of the cities in your state. Hence, you will need a measuring device to prove this point.

The Weather Instruments Composition

As a weather instrument, the rain gauge is simple in style yet very useful and practical. The typical and conventional device is mainly composed of three parts. They are the long and thin cylindrical tube, the funnel that is set atop the graduated cylinder, and the container housing. There is usually an outer container which envelops the cylindrical tube to ensure that even the excess water rain is collected.

It is often said that when it rains, it pours. Thus, this device makes sure that it collects everything. The reading can be inaccurate if the device fails to get some of the water rain. Thankfully, the experts have thought of putting the smaller cylinder into a bigger container.

How it Works
When the rain falls, the water goes directly through the funnel. It serves as the passageway especially because it is positioned on top. As the first base, it collects the water rain and determines the level of precipitation through the lines that signify the measurement which can either be in millimeters or inches.

Of course, there is a limit to the amount of rainwater which the cylinder can accommodate. The main thing to take note of is that you must apportion a certain amount of time before the final measurement should be taken.

Say for example, it started to rain in the morning. Your stipulated time is about 24 hours. Meaning, if the cylinder overflows with water, you can take it down but you dont have to rely on the first measurement. You should measure everything, including the excess rainwater that has been caught by the bigger container, after 24 hours. That becomes your final measurement.

Remember that you have to put the excess water from the larger container into the empty cylinder so you can see the appropriate level based on the millimeter markings visible in it. Do this over and over again until the large container is emptied and you have already recorded your final measurement.

This is how a conventional and basic rain gauge works. Due to the immense innovation in todays modern technology, some other types of this instrument have been made available. Some have parts which have been enhanced from being too conservative to being convenient while the others feature a high-tech nature. One good example is the wireless rain gauge which allows indoor monitoring.

Overall, the rain gauges may include a variety of methods for them to function. Yet, what remains the same is that they all have the same goal and that has something to do with collecting the rainfall and determining the amount or level which has fallen on a particular place at a given time frame.