President Donald Trump monitored Hurricane Harvey from the seclusion of his official mountaintop retreat on Saturday and into Sunday morning, sending a flurry of tweets before and after the powerful storm made landfall in Texas in an effort to reassure the public that he was fully in control of managing the first natural disaster since he took office.

“Closely monitoring #HurricaneHarvey from Camp David. We are leaving nothing to chance. City, State and Federal Govs. working great together!” Mr. Trump tweeted Saturday morning.

In an evening tweet, he said, “Wonderful coordination between Federal, State and Local Governments in the Great State of Texas – TEAMWORK

The White House said in a statement Saturday that Mr. Trump held a video teleconference briefing on the storm with Vice President Mike Pence, Cabinet members and senior staff back at the White House.  

Mr. Trump directed all departments and agencies to “stay fully engaged and positioned to support his number one priority of saving lives,” and the governors of Texas and Louisiana, the White House said.

Trump reminded his team that the full effects of the storm will be felt over the next few days with heavy rains and flooding. He also thanked all the volunteer and faith-based organizations that are providing assistance, and sent his thoughts and prayers to those who were affected.

Harvey was downgraded to a tropical storm on Saturday afternoon.

By Sunday morning, Mr. Trump was back on Twitter as rescue efforts were well underway in Houston amid what the National Hurricane Center called “catastrophic flooding in southeastern Texas.”

“Great coordination between agencies at all levels of government,” Mr. Trump wrote Sunday morning. He added, “Continuing rains and flash floods are being dealt with. Thousands rescued.”

Mr. Trump also acknowledged the seriousness of the storm, later tweeting: “Many people saying that this is the worst storm/hurricane they have ever seen. Good news is that we have  great talent on the ground.”

The White House said Mr. Trump had received multiple storm updates on Friday and Saturday from chief of staff John Kelly, formerly secretary of the Department of Homeland Security, where the Federal Emergency Management Agency is housed. The White House released photos of Trump presiding over Saturday’s video teleconference from the Camp David presidential retreat in Maryland’s Catoctin Mountains with his advisers gathered in the White House Situation Room.

A businessman inexperienced at managing a natural disaster, Mr. Trump has been mindful of his image during the storm.

He tweeted a photo of himself in the Oval Office on Friday, with his desktop covered by color-coded papers. He was joined by Kelly and homeland security adviser Tom Bossert.

Mr. Trump’s tweets also covered conversations he had with the governors of Texas and Louisiana, urgings for the public to follow the advice and orders of their state and local officials, and his decision to declare that a major disaster exists in Texas, which expedites the flow of federal money for rebuilding after the storm.

Bossert told reporters that “this is right up President Trump’s alley” when asked Friday what the president needed to do to project leadership during the storm.

“Not only has he shown leadership here, but his entire focus has been on making America great again,” Bossert said. “He is focused on the Americans that voted him into office. He’s focused on the Americans that didn’t vote him into office. He’s focused on effecting positive change in this country. And when we go in and brief him on the preparations for this hurricane, he is acutely focused on making sure that — and just the right thing, by the way — that the American people in the storm’s path have what they need.”