"It's the biggest ever, they are saying it is the biggest, it's historic," Trump said, addressing a White House press conference a day before he travels to the Lone Star State with First lady Melania Trump.
"There's probably never been anything like this," Trump said of Tropical Storm Harvey, which hit the Gulf Coast at the weekend and inundated the Houston region.
"I've heard the words 'epic,' I've heard 'historic.' That's what it is," he added.
The US leader earlier indicated his team had already been in contact with Congressional leaders to discuss relief for the millions of people affected by tropical storm Harvey, which is barrelling along the Texan coast toward Louisiana.
"We're dealing with Congress," Trump said, speaking from the Oval Office, "as you know it's going to be a very expensive situation. We want to take care of the people of Texas and Louisiana when that happens."
Since making landfall, Harvey has soaked Houston, America's fourth largest city and the capital of the country's vast energy industry.
Trump has been eager to show he is on top of the situation, and that he will not make the same mistakes as previous presidents in botching the federal response.
"Things are being handled really well, the spirit is incredible of the people and the coordination between all of the different services, as you know, has been going very well," he said.
Trump's trip to Texas comes much more quickly than other presidents may have dared. Along with a high-impact presidential trip comes the risk of hampering recovery efforts and tying up resources.
But the recently inaugurated president indicated he may make a return trip to the region this week.
"We may actually go back on Saturday, depending on where the storm goes we may also go to Louisiana on Saturday."
Since the crisis began last Friday, Trump has seized on his role marshalling the federal response, issuing a disaster declaration for Texas and neighboring Louisiana and deploying 8,000 officials throughout the flood zone.
During a busy weekend, the White House released photos of the president -- decked in a USA cap -- huddling with aides, liaising with cabinet secretaries to discuss what he called a "once in 500 year flood."
A steady stream of tweets have sought to show that the president, who spent the weekend at the bucolic presidential retreat of Camp David, was well apprised and in control.
The full impact of the ongoing storm is unknown, but up to 30,000 people are expected to need emergency shelter, and up to half a million some form of disaster relief.