At least six people were killed and two others were missing in North Carolina on Thursday as flash floodwaters swept away roads and bridges, the authorities said.
The state bore a heavy brunt from the same weather system as Tropical Storm Eta, with some areas receiving about 10 inches of rain.
One of the hardest-hit areas was Alexander County, about an hour north of Charlotte, where emergency responders said they found the bodies of three people and evacuated 31 others from a campground.
As of 4 p.m., an adult and a child were still missing from the Hiddenite Family Campground, said the authorities, who reported that a fourth person in Alexander County had been killed in a car when floodwaters destroyed a bridge.
“It is hard on the rescuers, especially when you have to break the news to the family,” Chris Bowman, the county’s sheriff, said during a news conference on Thursday afternoon.
Alexander County was one of five counties in North Carolina that declared a state of emergency on Thursday, according to Steve Powers, the state’s deputy director of emergency management. The others were Burke, Catawba, Iredell and Yadkin.
At least four bridges and 50 roadways in Alexander County were breached by the floodwaters, the authorities said. Amber Roberts, a television reporter for Fox 46 Charlotte, was live on the air when one of the bridges collapsed in front of her. A video of the journalist’s close call drew widespread attention on social media.
“This is incredibly — ” Ms. Roberts said, screaming as the bridge gave way, “scary. OK, we’re backing up. We’re backing up. So thank God that we are backing up.”
The other two fatalities in the state occurred in Iredell County, which is also north of Charlotte and borders Alexander County.
At 5:45 a.m., the driver and passenger in a Ford Ranger pickup were killed when their vehicle hydroplaned on Highway 115 (the Wilkesboro Highway), crossed the center line and collided with an oncoming Jeep Wrangler, the North Carolina State Highway Patrol said. Officials said that the pickup was traveling too fast for the conditions and that both men were not wearing seatbelts.
The flooding was a result of a cold front in the area mixing with “deep tropical moisture” as a result of Tropical Storm Eta, which battered both coasts of Florida for days as it moved north, according to a meteorologist with the National Hurricane Center.
“This is a direct association with Eta,” the meteorologist, Dennis Feltgen of the National Hurricane Center in Miami, said.
The cold front normally “would trigger some rain,” Mr. Feltgen said. “We’re all used to that. But unfortunately Eta is in the position where all that deep tropical moisture” from the storm “is getting pulled in ahead of the front and it’s going right across the Carolinas and southeastern Virginia.”
In Charlotte, rescuers evacuated 143 students from the Charlotte Corvian Community School after floodwaters overwhelmed the building on Thursday, the Charlotte Fire Department said on Twitter. There were no injuries.
In another part of the city, a man riding a bike with his wife spotted a man trapped by rising water, before firefighters came to the rescue.
“He was up to his neck, holding onto a tree,” the witness told television station Fox 46. “So we realized he was in trouble and I called 911.”
By Thursday afternoon, Eta was about 115 miles south-southwest of Charleston, S.C., though its impact reached far beyond.
“Remember this is not a dot on a map,” Mr. Feltgen said. “These are large storms with impacts over a large area. Eta is a classic example.”
When Eta passed over the Florida Keys late on Sunday, Mr. Feltgen, who lives 175 miles north in Broward County, said he personally saw the storm’s impact.
“I got 18 inches of rain” and “I’ve never seen my neighborhood flood,” he said. “This was a first.”