This year is on pace to see the most deaths since 130 people were killed in 1998, the eighth highest total since 1950, according to the National Weather Service. The record is 519 tornado-related deaths in 1953.
In Picher, the devastation was complicated by the town's status as one of the most polluted Superfund sites in the nation. But Miles Tolbert, the Oklahoma secretary of the environment, said he did not think there was an immediate public health hazard to the 800 residents. He did say more testing is needed to be certain.
Long-term exposure to lead dust poses a health risk, particularly to young children.
On Saturday, a tornado with the second-strongest rating killed six people, destroyed a 20-block area and blew dust off mountains of mining waste, or chat piles.
"You can look at the chat piles and see that a lot of the material has blown off," said John Sparkman, head of the Picher housing authority. "We went up on a chat pile an hour and a half after the tornado hit, and you could see dust blowing fine material all over the place from that vantage point."
In all, 22 people were killed in the tornado outbreak in Oklahoma, Missouri and Georgia.
Meanwhile, law enforcement officers and the Oklahoma National Guard patrolled the Picher overnight into Monday to prevent looting, said Michelann Ooten, spokeswoman for the Oklahoma Department of Emergency Management.
National Weather Service assessment teams determined the twister that hit Picher had an EF-4 rating, the second highest rating, and was 1 mile wide at its widest point, meteorologist Mike Teague said Monday.
The tornado's winds were estimated at 165 to 175 mph, and the damage track stretched 74 miles - 29 in Oklahoma and another 45 in Missouri, where 15 people were killed.
"These storms are fairly rare to be that strong. The devastation was nearly complete in a few areas," Teague said. "Albeit isolated, there were some sections of neighborhoods where houses were just completely taken off the foundation. Gone."
The tornado could be the ultimate incentive for those 800 or so residents who have been reluctant to leave, now that most of their homes have been ruined, Sparkman said.
One of those residents, Sue Sigle, had been hoping the government would offer more money for her home before she moves away from this pollution-scarred town. Then the tornado came.
As she began the task of salvage Sunday, Sigle kept a smile on her face, noting that she was fortunate to be visiting family in Missouri when the massive twister hit.
"I'm OK with everything," Sigle said. "The Lord is going to take care of anything. ... I was going to move anyway. I guess I'll just have to move sooner."
That sense of inevitability appeared to grip residents as they picked through the remnants of their homes. The lead and zinc mines that made Picher a booming town of about 20,000 in the mid-20th century closed decades ago; leftover waste has turned the area into an environmental disaster.
Gov. Brad Henry, who toured the area by air and on foot Sunday, said the buyout program won't stop just because homes were leveled. He went so far as to say he would "guarantee" that those awaiting buyouts who lost their homes would be treated fairly.
"We will make sure the people get the assistance that they need," Henry said.
Because of Picher's Superfund status, the Federal Emergency Management Agency is unlikely to grant assistance to homeowners to rebuild in the town, said Oklahoma Emergency Management Director Albert Ashwood. But he echoed Henry's assurances about the federal buyout program, which is funded by the Environmental Protection Agency.
One of the homes those crews likely will examine will be that of Jeff Reeves, 43, who has followed his grandfather and father as Picher's fire chief. He has lived in Picher all his life and has watched it slowly decline.
"With everything else that's going on here, I'm not sure there is a recovery," he said.