"This is, if not the largest, it has to be categorized as one of the largest disasters America has ever faced,"Texas Gov. Greg Abbott declared at a press conference Monday afternoon.

Houston's main water-way, Buffalo Bayou, shows over 30 inches of rain and it's about to get a lot worse. Buffalo Bayou is the main waterway that snakes through the heart of Houston, and the water levels of two reservoirs that feed into it are particularly concerning.

"The reality is the water is continuing to rise," Mr. Turner said. "The water level along Buffalo Bayou in all likelihood will increase."

Forecasters say Harvey will move slowly to the northeast throughout the week and shower some parts of the state with another 15 to 20 inches of rainfall by the end of Thursday. Additionally, The Post reports that certain areas to the west of Houston could see as much as 50 inches of rain by the time the storm is over — which would be the largest recorded total in Texas history.