How much is an inch of rain? A one-inch rainfall is fairly unusual, and it is a lot of water. Why do you need to know how to measure rainfall? The weatherman can tell you how much rainfall you have had in your area; this is not always accurate. The weatherman gets his information from a central location, probably the local airport. Mother Nature being fickle will make it rain in one place and not in another. This is important for the growth and maintenance of gardens, flowers and crops. You need to be aware of the rainfall in your backyard. Measuring rainfall is easy.
Purchase a rain gauge. Make sure it has a mounting bracket to attach to a fence or post. It will consist of a clear straight sided cylinder, usually plastic.
Mount the rain gauge away from trees, buildings, or other structures that could obstruct the rain from going into the gauge.
The measuring tube is calibrated with numbers on the side allowing you to measure rain to one hundredth of an inch, it is also magnified by a factor of 10 making it easier to read.
Meniscus. As the rain water fills the measuring tube, a curved surface called a meniscus if formed. Read the base of the meniscus when you take your measurements.
No rulers. Do not use a ruler to measure rainfall; it is not calibrated to measure the water in the tube.
Wait for the rain to completely stop before you check your rain gauge.
Leave the measuring tube in the bracket while you check the lines on the side to determine how much rain has fallen. The measuring tube should be emptied following each reading.
Now you will be able to record the exact amount of rain that has fallen in your back yard. You will also be able to control the growth of your garden, by adding additional water if needed.