Tropical Storm Harvey is slowly making its way toward New Orleans.
Harvey is threatening to bring as much as 250-millimetres of rain to an area that is preparing for the 12th anniversary of Hurricane Katrina.
Meantime, authorities in Houston are worried the worst might be yet to come as more rain is expected, on top of the more than 700-millimetres that has already fallen in some places.
So far Houston police have rescued more than 3,000 people and more than 100,000 are without power.
President Trump is promising a quick response from the federal government for relief efforts.
Hurricane Harvey is the first major natural disaster of Trump's presidency.
He plans to visit Texas today.