Residents of southern US states along the Mississippi River are bracing for the flooding that swamped communities from the Ohio River Valley to eastern Oklahoma during the week, causing thousands of evacuations and killing at least 31 people.
Officials in Louisiana are checking levees daily, and Exxon Mobil has decided to shut its 340,571 barrel-per-day refined products terminal in Memphis, Tennessee, as floodwaters threatened to inundate the facility, just south of the city.
"All that water's coming south and we have to be ready for it," Louisiana Lieutenant Governor-Elect Billy Nungesser told CNN.
"It's a serious concern. It's early in the season. We usually don't see this until much later."
Workers in southwestern Tennessee were preparing sandbags yesterday in the hope of limiting damage when the Mississippi crests at Memphis next week, emergency management officials said.
Flooding in the US Midwest typically occurs in the northern spring as snowmelt swells rivers. But freezing temperatures that have followed the rare winter flooding have added to regional woes.
Most of the deaths in Illinois, Missouri, Oklahoma and Arkansas have been caused by people driving into flooded areas after days of downpours.
The dead included a central Illinois teenager whose body was recovered near where a truck in which he was riding was found the day before. Another teen from the truck was still missing.
Authorities also continued searching for country singer Craig Strickland, who had gone duck hunting on an Oklahoma lake in stormy conditions. His friend, Chase Morland, was found dead during the week.
Twelve Illinois counties have been declared disaster areas, and Governor Bruce Rauner has ordered Illinois National Guard troops into flooded areas in the southern part of the state to mitigate flood damage and help with evacuation efforts.
All that water's coming south and we have to be ready for it.
The Mississippi is expected to crest at Thebes, in southern Illinois, at 14m later in the week, more than 50cm above the 1995 record, the National Weather Service (NWS) said.
Flood warnings were also in effect for parts of Texas, Oklahoma, the Carolinas, Alabama and Kentucky, the NWS said, while major flooding was occurring on the Arkansas River and its tributaries in that state.
Dozens have died in US storms, which also brought tornadoes, unusual for winter. They were part of a wild worldwide weather system over the Christmas holidays that also caused severe flooding in Britain.
More than 100,000 people were forced to evacuate their homes in areas around Paraguay, Uruguay, Brazil and Argentina after floods due to heavy summer rains caused by an El Nino system, authorities said.