Storms Batter Houston, Leaving at Least 4 Dead and Hundreds of Thousands Without Power

Four people were killed and nearly a million customers along the Gulf Coast were without power on Friday after intense thunderstorms swept through Texas the night before, bringing heavy rain, destructive winds and dangerous flooding to portions of the state that had already been inundated this month.

The storm blew out windows, caved in the wall of a building and downed power lines across Houston, as powerful winds tore through downtown. Of the people who died, at least two were killed by falling trees, and one was killed in an accident involving a crane that toppled over in strong winds, according to Samuel Peña, the city’s fire chief.

As officials surveyed and began to clean up the damage, Mayor John Whitmire of Houston said at a news conference on Friday morning that investigators were trying to determine whether a fifth death was related to the weather.

Mr. Whitmire said it could take several weeks for power to be restored to some customers.

Much of Houston was battered by winds of speeds up to 100 miles per hour, rivaling speeds recorded during Hurricane Ike, which caused widespread damage across a wide swath of Texas, including in Houston, in 2008.

“It was fierce, it was intense, it was quick,” Mr. Whitmire said of the latest storm, “and most Houstonians didn’t have time to place themselves out of harm’s way.”

Houston’s public school district said all schools would be closed Friday. Emergency responders warned people to stay home, saying that many roads were still impassable and that most traffic lights were out across the city. Firefighters still had to remove a live power line from a major highway.

Before the storm, the National Weather Service office in Houston had warned people to take cover and brace for winds up to 80 m.p.h.

Forecasters also issued a tornado warning for the area as well as a special marine warning for the area including the Galveston Bay. On Friday, Jeffry Evans, a Weather Service meteorologist, said a tornado had not been confirmed.

As of 11 a.m. local time, about 770,000 customers were without power across Texas, most of them in the Houston area, according to Poweroutage.us, which aggregates data from utility companies across the country. CenterPoint Energy, the provider in southeastern Texas, said it had received reports of downed power lines and advised customers that its call centers were overwhelmed. Another 97,000 were without power in Louisiana.

Forecasters warned that the weekend would also bring “sweltering heat” to southern Texas. Temperatures were expected to reach the upper 70s in the Houston area on Friday, but those without power, and air conditioning, would experience 90-degree temperatures through the weekend and into next week.

Lina Hidalgo, the top executive of Harris County, which includes Houston, said public libraries were open to serve as cooling centers.

Local news broadcasts reported considerable damage in downtown Houston, with the force of the winds shattering the windows of high-rise towers, twisting metal sign posts and felling trees on the street. The storm tore through the walls of at least one building, leaving piles of bricks, and falling debris also crushed cars. It left main streets blanketed in crushed glass and debris.

The Weather Prediction Center said that showers and thunderstorms were expected across a broad part of the eastern United States on Friday. Moderate to heavy rain would likely focus in an area over the Lower Great Lakes, the Appalachians and the Gulf Coast.

An especially heavy downpour could have an impact in parts of Southern Mississippi and Alabama, it said, and there was still a risk of excessive rain over the already saturated central Gulf Coast states. The risk of severe thunderstorms was slight, but could affect about seven million people living there, the service said.

Flash flood warnings were in effect on Friday morning for parts of Mississippi and Louisiana, as a severe thunderstorm brought hail the size of golf balls to the city of San Patricio, Texas. The Weather Service office in Corpus Christi, Texas, warned residents to move inside because of “continuous cloud-to-ground lightning.”

Portions of Harris County, including areas near the San Jacinto River, were already hit with major flooding earlier this month. The flooding prompted Ms. Hidalgo, the Harris County executive, to issue a disaster declaration that would bring federal aid to residents who were affected by the storms.

Isabella Kwai and Christine Hauser contributed reporting.