It rained so much in Houston that NWS added new colors to rainfall maps

When you have 30 or more inches of rain falling over only a few days, adjustments have to be made. The National Weather Service is no exception.

The weather forecasters have had to add new colors to their weather maps, Mashable reported.

NWS added a light purple, or lavender, layer to show what it is calling "unfathomable rain," or greater than 30 inches.

And more rain is on the way.

This isn't the first time a new color was needed to illustrate a weather phenomenon. In 2013, Australia needed another color for a deadly heat wave that blanketed the island continent, the Guardian reported.

Experts say 12 trillion gallons of rain has fallen in Texas during Harvey.