Strong winds and rain from Tropical Storm Beryl on Monday killed at least three people in southeast Texas, closed oil ports, halted about 1,000 flights and knocked out power to more than 2 million homes and businesses.

Beryl, the first Category 5 hurricane of the season, weakened after slamming into the coastal city of Matagorda, Texas, producing dangerous storm surge and heavy rain before moving through Houston, the US National Hurricane Center (NHC) said.

The storm, which is expected to weaken quickly as it moves inland, carved a destructive path through Jamaica, Grenada and St. Vincent and the Grenadines last week. At least 13 deaths have been reported so far in the Caribbean and Texas.

A 53-year-old man and a 74-year-old woman died Monday in two incidents caused by trees falling on their Houston-area homes, Harris County officials said. They added that a third person drowned.

In the state, which is the largest producer of oil and natural gas in the United States, oil refining activity has slowed and some production sites have been evacuated.

“Storm surge and heavy rain threaten life in parts of Texas. Damaging winds continue along the coast, with strong winds moving inland,” the NHC said.

Following warnings that the storm could be deadly for communities in its path, residents rushed to board up windows and stock up on fuel and other essentials.

Strong winds and heavy rain lashed cities including Lake Jackson, Galveston, Sargent and Freeport before dawn, television footage showed.

By late morning, several fallen trees blocked roads in Houston as the worst of the storm passed, with persistent winds and some flooding on roads leaving major highways impassable.

In a video posted to social media by a local Houston ABC station, workers wearing life jackets and a fire truck with a ladder rescued a man in a truck on a flooded section of highway.

At a news conference, Houston Mayor John Whitmire urged people to take shelter. He noted that floodwaters in much of the city had exceeded 25 centimeters.