Millions of Texans are facing days of torrential rain and "catastrophic flooding" in the aftermath of Hurricane Harvey.

Up to 40 inches (102cm) of rainfall is predicted in some areas, with the mayor of Houston - the fourth most populous city in the US - telling people to prepare for a "major water event".

Sylvester Turner also advised people to stay off the roads, cautioning residents: "This is serious".

Image: A vehicle navigates a street flooded by rain in Galveston, Texas

Texas Governor Greg Abbott warned of the "potential for very dramatic flooding", expanding the state's declaration of emergency from the original 30 counties to 50.

The category 4 hurricane, which was later downgraded to a tropical storm, is forecast to bring deluges of rain and flash floods as it slowly moves inland.


One man died when his house caught fire in Rockport, a small coastal town which has been particularly badly hit by the storm. A woman in Houston who appeared to have gotten out of her vehicle in high water was also killed.

Image: The National Weather Service (NWS) is predicting major river flooding

Buildings were destroyed and boats sunk in the marina as the small community was hit with the full force of the storm.

One resident described seeing tornadoes rip up trees and lift ponies into the air before scooping up a caravan with an entire family inside.

Hundreds of thousands of people across the state have also been left without power, with the electricity grid damaged by the storm.

Image: Up to 35 inches of rain is possible over southeast Texas in the coming days. Pic: NHC

Mobile phone networks and internet services have also been wiped out.

Sky News Correspondent Siobhan Robbins, who is in Rockport, said: "The hurricane has left its scar on every street here, and now flooding threatens.

"While this town is determined to rebuild, the true extent of what and who they've lost still hasn't been revealed."

Emergency agencies have warned that recovery from Harvey could take years.

Donald Trump has been monitoring the storm's path from Camp David, tweeting his praise for the teamwork of the Texan federal, state and local government and commenting on the "record setting rainfall".