We all see the photos/videos of running washes and heavy rain but just how much water is falling from the sky?

Using Maricopa County Flood Control rain gauges and some personal weather stations to fill in the gaps, on average, approximately 1.90" fell over the nearly 16,000-acre area noted in the yellow box (image above) on July 28, 2022.

Using the fact that there are ~27,154 gallons of water when one inch of rain falls on an acre of ground, that brings us to a total of ~820,219,154 gallons of water that fell in a very short period of time across the area.

To put this into a little more context, that is enough water to fill the swimming pool in Chase Field 96,496 times. In other words, a lot of water.

As you can see, even though an inch of rain does not seem like a lot, it adds up quickly resulting in running washes and flooding.