Rainstorms can be localized or widespread.

A localized heavy summer rainstorm in Colorado.

Here is a classic rainstorm during the summer, as that is when more localized storms occur. Other rain events are more "frontal" in nature, with large formations of featureless and uniform nimbostratus types of clouds bringing precipitation over a large area. But often you see a landscape similar to the one in this picture, with rain falling in a localized area (and often moving right toward your picnic) from a relatively small cloud. The sheets of rain are easily seen. Often these storms are intense but brief.

How much water falls during a storm such as this?

You might be surprised at the number of gallons of water that fall from the sky in even a small but intense storm. One inch of rain falling on just a single acre results in 27,154 gallons of water on the landscape.  If you'd like to know how much water falls during a storm, use our "Interactive Rainfall Calculator (English units  |  Metric units)" to find out; enter an area size and rainfall amount, and see how gallons of water hit the ground.