Speaking at a televised news conference in Austin, Governor Abbott said state and other agencies remained active in search and rescue efforts. “We don’t have any information right now that we can confirm” about fatalities, he said.

He warned Texans to be vigilant and to stay away from rising water, noting that it can be far deeper, with swifter currents, than it may appear.

“Turn around, don’t drown. Don’t risk your life,” he said. “The most important thing all Texans can do is to put your life and the protection of your life first and foremost.”

He said agencies were focused on supporting evacuees from Corpus Christi and elsewhere, and on getting supplies, such as food, water and ice, to areas that needed it. — JOHANNA BARR in New York

Hundreds of thousands are without power.

The storm remained a hurricane well after landfall, and conditions, including tornado warnings, made it difficult for the authorities to begin even preliminary damage assessments.

More than 250,000 customers were without electricity early Saturday, a figure that was likely to increase. Corpus Christi urged people who were still in the city to boil water.

Images and videos on social media showed substantial damage to buildings, including roofs and walls pulled away. Power lines were toppled, and phone service was down.