Hurricane Matthew is gone, but the disaster it unleashed will slowly unfold this week as rivers across eastern North Carolina rise to levels unseen since a similar deluge flooded thousands of homes and businesses during Hurricane Floyd in 1999.

Emergency planners are now using models that can pinpoint exactly how high the rivers can get and which buildings will be flooded days in advance. But they can't predict whether dams and levees will bust from the stress of more than a foot of rain in some places. At least one already has.

In Lumberton, a levee broke overnight and crews scrambled to rescue 1,500 people. Most of them were in knee deep water, but there were people on rooftops waiting for boats or helicopters, North Carolina Gov. Pat McCrory said.

Evacuations were ordered in cities along three different rivers. Some rivers were expected to be at record levels Friday - six days after Matthew's rains ended.

State resources are stretched to their limit, McCrory said.

"If you've been told to evacuate, then evacuate. If you don't we have to divert resources to the area to save you," the governor said Monday.

Immediately after Saturday's rains, thousands of people found themselves suddenly trapped in homes and cars during the torrential rains. Rescuers in Coast Guard helicopters plucked some of them from rooftops and used military vehicles to reach others, including a woman who held on to a tree for three hours after her car was overrun by flood waters.

The storm killed more than 500 people in Haiti and at least 21 in the U.S. - nearly half of them in North Carolina. Most were swept away by flood waters.

At least two of the five people reported missing in North Carolina have been found. McCrory and others fear the death toll may rise though, as impatient people drive around road barricades into swiftly moving floodwaters.

The National Hurricane Center issued its last advisory on Matthew at 5 p.m. Sunday, when the storm was about 200 miles off the North Carolina coast.

Princeville, a town of 2,000 that disappeared in the waters of the Tar River during Floyd, was evacuated Sunday. The river was expected to rise to 17 feet above flood stage by late Monday - a level not seen since Floyd, which was another storm whose eye brushed by North Carolina's coast but poured 15 to 20 inches of rain inland.

David Bullock's sister called him as he bought lottery tickets and told him police were knocking on doors in Princeville saying they had to go. He rebuilt his home after the 1999 flood.

"If I get flooded again, I can't take it. I can't go back and take the expense. If I get flooded again I'm going to say, 'It's yours, I'm gone,'" Bullock said.

Floyd killed 35 people in North Carolina, destroying 7,000 homes and damaging 56,000 others, causing more than $3 billion in damage.

Several sections of Interstate 95 - the main artery linking the East Coast from Florida to Maine - were still closed in North Carolina.

The levee break in Lumberton County poured even more water on the interstate and McCrory said it is impossible to determine when the highway might reopen.

The Lumber River in Lumberton crested 4 feet above its record level Sunday afternoon and was forecast to remain above its previous record until at least next Saturday.

At least 38 school districts in the state closed classes, some for at least the entire week.

Matthew's flooding was made worst by heavy rains in September. Many areas east of I-95 got at least twice their normal amount of rain in September, in part because the remnants of Tropical Storm Julia parked off the coast for several days.

In addition to the 10 deaths in North Carolina, there were four in Florida and three each in Georgia and South Carolina. One death was reported in Virginia on Monday.

Some were killed by falling trees, others by carbon monoxide fumes from a generator. One 66-year-old man near Columbia, South Carolina, died at a nursing facility when he got pinned under his electric wheelchair in water.

Nearly 1 million homes and businesses still did not have power Monday morning in North Carolina and South Carolina. Authorities in coastal Georgia and South Carolina warned residents it may take days or even weeks to restore electricity and clean up all the debris left behind by the winds and ocean flooding.

Matthew plowed into desperately poor Haiti with winds of 145 mph and sideswiped hundreds of miles of the U.S. coastline from Florida through the Carolinas, its eye staying far enough offshore that the damage in many places along the coast was relatively modest. A shift of just 20 or 30 miles could have meant widespread devastation nearer the ocean.

An estimated 2 million people in the Southeast were ordered to evacuate their homes as Matthew closed in.