WASHINGTON — Over the long weekend, President Trump monitored Hurricane Dorian from a golf cart at his club in Virginia, calling for regular updates from an aide trailing him around the course. By 8 p.m. Monday, as Dorian churned toward Florida and Mr. Trump’s boarded-up Mar-a-Lago resort, the president had golfed twice and since Saturday morning pelted the American public with 122 tweets.

As he has done during other hurricanes, Mr. Trump awaited landfall by assuming the role of meteorologist in chief, adding weatherman-style updates to a usual weekend routine of attacking his enemies, retweeting bits of praise and critiquing the performance of his cable news allies.

Starting with his first weekend tweet at 7:45 a.m. Saturday, Mr. Trump’s Dorian-related tweets were delivered with the speed of a hailstorm.

With his reality-show approach to the presidency, Mr. Trump has a habit of weighing in on the day’s most-covered news stories with his own running commentary. As Dorian approached, Mr. Trump switched into town-crier mode, updating the public on what he had learned — or, what he thought he’d learned — from government officials as Dorian threatened the coast of the state of Florida, where he has owned property for decades.