Harvey weakened to a tropical storm Saturday as it moved along the Texas coast, but it saturated the state with torrential rains. The National Hurricane Center warned that an "extremely serious flooding event" was unfolding and that the storm was "barely moving."
The storm, the most powerful storm to hit Texas since 1961, blew onto shore as a Category 4 hurricane, bringing with it destructive 130 mph winds and the potential for severe flooding. By Saturday afternoon, it was downgraded to a tropical storm, but still posed a threat.
Texas Gov. Greg Abbott on Saturday expanded his disaster declaration from 30 to 50 counties, saying he would activate 1,800 military personnel to help with cleanup efforts. He added that 1,000 people are involved with search and rescue operations.
U.S. Health and Human Services Secretary Tom Price declared a public health emergency in response to the storm, waiving certain documentation requirements for Medicare recipients who may not have their health records on them. The provisions of the declaration take effect at noon ET on Monday, but are retroactive to Friday, HHS said in a statement.
The NHC has said it expects Harvey to cause "catastrophic flooding" as the storm lurches along the Gulf Coast over the next few days. Some areas could get as many as 40 inches of rain.
One death, in the town of Rockport, Texas, was reported as officials continued to grapple with the storm's effects. Authorities said it would take hours before damage was fully assessed. More than 300,000 people were without electricity. The mayor of island city Port Aransas, Texas, said there was "massive" damage, but authorities still weren't able to determine the extent of the storm's destruction.
Federal Emergency Management Agency Administrator Brock Long tweeted that the agency was supporting Texas state authorities in their efforts to contend with the storm.
Hazards from the storm are only likely beginning, a National Hurricane Center analyst told the Associated Press, even after Harvey left a track of devastation. Images of the storm's destruction filled up social media.
Harvey, the most powerful storm in over a decade to hit the mainland United States, made a first landfall northeast of Corpus Christi, Texas, around late on Friday with maximum winds of 130 miles per hour. It then made a second landfall nearby three hours later.
Harvey was downgraded to a tropical storm by the National Hurricane Center Saturday afternoon. As of 5 pm ET, Harvey, packing sustained maximum winds of 65 mph, was parked about 45 miles west-northwest of Victoria, Texas.
Corpus Christi city authorities tweeted Saturday that residents could return to their homes.
President Donald Trump said late Friday night that he signed a disaster declaration at the request of Abbott, the Texas governor. Saturday morning, the president tweeted words of encouragement for the Federal Emergency Management Agency while noting that he was monitoring the situation from Camp David.
In a later tweet, Trump thanked volunteers helping with relief efforts
As the storm crept slowly along the Texas shoreline, Houston's sprawling, flood-prone metropolitan area prepared for a deluge. The city's mayor warned residents that the area could be hit with two to three feet of rain over the next few days.
Houston has received about 16 inches of rain as a result of Harvey; about 20 inches has fallen on neighboring Corpus Christi. Areas between the two cities could see another 20 to 30 inches of rain, Abbott said earlier Saturday.
Harris County Judge Ed Emmett, the chief administrator of the county that includes the city of 2.3 million, said flooding so far was a "minor issue," but warned that "we're not out of this."
In New Orleans, officials began to prepare for the storm. On Saturday, the city's police department said it would begin placing traffic barricades in anticipation for Harvey.
The Associated Press, NBC News and Reuters contributed to this report.