A truck driver walks past an abandoned truck while checking the depth of an underpass during the aftermath of Hurricane Harvey August 28, 2017 in Houston, Texas. Brendan Smialowski/AFP/GETTY

Hurricane Harvey made landfall in Texas as a Category 4 Hurricane Friday, and has since calmed down into a tropical storm. As of Tuesday, the storm has dropped over 50 inches of rain east of Houston making it the single greatest recorded rain event in the continental U.S. ever, according to the Washington Post Wednesday.

And it’s not over yet.

Greg Carbin, chief of the National Weather Service's (NWS) forecast operations branch said that Texas still has a few more days of rain.

“That entire rain shield and rain bands associated with Harvey will begin to transition to the north and east out of the Houston area … hopefully, by late [Tuesday], we’ll see most of that rain move out of the Houston area,” said Carbin to NPR, Tuesday. “Unfortunately there is still much more rain to come up across Beaumont, Port Arthur, Lake Charles and even to New Orleans. That’s still going to be a problem as the rain fall moves across those areas through [Tuesday] and [Wednesday].”

Over 11 trillion gallons have fallen on Texas, according to CNN Tuesday.

Discounting climate change, the Space Science and Engineering Center at the University of Wisconsin at Madison calculated that the rain that has fallen in parts southeast Texas should only happen once every 1,000 years.

“The 3-to-4 day rainfall totals of greater than 40 inches (possible 50 inches in locations surrounding Santa Fe and Dickinson) are simply mind-blowing that has lead to the largest flood in Houston-Galveston history,” reported the NWS.

The storm has killed at least 13 people, according to the New York Times Tuesday, including one police officer. Sgt. Steve Perez, 60, was killed while on duty Sunday, according to Houston’s mayor, Sylvester Turner.

The Houston Police Department said Tuesday that it has rescued more than 3,500 people and the Fire Department has made over 400 rescues. The Harris County Sheriff’s office reported that it has rescued over 2,000 people so far. Harris County surrounds Houston.

President Donald Trump visited Texas Tuesday. Trump declared a state of emergency for the state Friday, and has already declared a state of emergency for Louisiana, where the storm will head next.

“It’s a real team, and we want to do it better than ever before,” said Trump during a meeting with emergency officials in Corpus Christi, Texas. “We want to be looked at in five years, in 10 years from now as, this is the way to do it.”

Trump also addressed a crowd outside the Corpus Christi firehouse where the meeting took place,

“What a crowd. What a turnout,” he said.

Texas Gov. Gregg Abbott has deployed all 12,000 members of his states National Guard.