Rockport Mayor Patrick Rios had blunt words for those determined to stay, telling them to “mark their arm with a Sharpie pen, put their social security number” -- to identify them if they were found dead.

and perhaps a year's worth of rain falling in just four or five days could prove deadly.

Supermarket aisles were stripped bare, homes and shops had boarded up windows. The NHC warned of the “complete destruction of mobile homes,” of many buildings “washing away,” and some areas being left “uninhabitable for weeks or months.” Some 213,000 customers in the storm region were left in the dark after Harvey struck, the local utility company, Ercot, said Saturday. “Much road debris and downed power lines,” Corpus Christi police said via Twitter. “Most traffic lights are out. Please be patient.”

Many residents who fled the worst-affected areas headed for the city of San Antonio where temporary shelters run by the fire department. “I felt like I didn't want what happened to the guys in New Orleans... I didn't want that to happen to me,” Michael Allen, an evacuee from Corpus Christi, told AFP.

“I only got what you see me with. Everything I had, I had to leave. Everything. It was bring it with me or lose my life and I felt like I should save my life.” Sheriff Frank Osborne of Matagorda County, where evacuations were mandatory, told local TV station KHOU that he would not risk the lives of his deputies “to save somebody that didn't leave when they were asked to.” In Louisiana, Governor John Bel Edwards issued an emergency declaration for his entire state, as authorities in New Orleans -- where Katrina did the most damage -- readied high-water rescue vehicles and boats.