Powerful storms have once again hit America's Midwest, with weak tornadoes touching down in isolated areas and severe thunderstorms rolling through several states, leaving dozens of people with minor injuries.
The US National Weather Service on Wednesday issued tornado watches and a series of warnings in a dozen states, from Texas northwest through the Mississippi River valley up to Ohio.
While there were no immediate reports of deaths from the latest round of storms, authorities did say that dozens of minor injuries had been reported after brief tornado touchdowns in Missouri and Indiana.
Wednesday's storms came after a deadly set of "supercell" storms killed at least 15 people in Arkansas, Oklahoma and Kansas on Tuesday. The deadliest tornado to strike the United States since 1950 hit the southwest Missouri town of Joplin on Sunday, killing at least 125.
Supercell thunderstorms are characterised by the presence of a deep, continuously-rotating updraft.
Towns hit by severe storms
On Wednesday, heavy rain, hail and lightning hit several inhabited areas, including Memphis, in Tennessee, but while clouds showed some rotation, there were no confirmed reports of tornadoes touching down in that state.
|Click to open an interactive map of the devastation
In southern Indiana, authorities said that at least 12 people were injured after a tornado touched down along a highway, east of the town of Bedford. Homes, barns and other structures were flattened by that storm.
"The guys on the ground there say it's a predominantly rural area, which is fortunate for the masses but of course not for the people nearby," said Brian Olehy of the Indiana State Police.
Earlier in the day, 25 people suffered from minor injuries when a tornado damaged several homes and businesses in the central Missouri city of Sedalia. Officials in that town said that most of the injured were able to get themselves to a hospital for treatment.
"Considering the destruction that occurred in Joplin - being that we're in tornado alley and Sedalia has historically been hit by tornadoes in the past - I think people heeded that warning," Kevin Bond, the Pettis County sheriff, said.
Authorities in Sedalia were forced to end the school year several days early because of damage to school buses. In one badly hit neighbourhood, law enforcement officials stood on corners and electrical crews worked to restore power, while residents cleaned debris and sifted through their belongings.
Joplin rescue operation continues
In Joplin, authorities were still engaged in a search and rescue operation, but they said that hopes of finding survivors was fading. None were found on Wednesday, while the number of people reported injured by the storm rose from 823 to more than 900.
Rescue crews sifted through the rubble with dogs trained to sniff out survivors, and many families also continued their desperate search for loved ones who have been missing since the storm.
Authorities have struggled to cope with massive destruction in the city, and a system of permits to allow residents back into their damaged homes and to prevent looting was abandoned on Wednesday, after long lines formed at access points.
|At least 125 people were killed in the storm that struck Joplin, the most powerful tornado to hit the
United States since 1950 [GALLO/GETTY]
Officials have reverted to keeping a strong police and National Guard presence, while allowing people free access to all damaged neighbourhoods. The tornado damaged or destroyed over 2,000 structures.
Structural engineers were sent inside the ruins of the St. John's Medical Center, which was crippled by the tornado, to see if the hospital could be saved.
The Joplin tornado on Sunday was rated an EF-5, the highest possible on the Enhanced Fujita scale of tornado power and intensity, with winds of at least 320 kilometres-per-hour.
Barack Obama, the US president, said he was "heartbroken" over the devastation wrought by the storm over the weekend and would visit the disaster zone on Sunday, following his four-nation visit to Europe.
Storms, meanwhile, are forecast to continue to hit the area, and authorities are advising residents to stay abreast of the latest weather warnings for their area.
"Unfortunately, this event will likely continue for some time," Mary Fallin, Oklahoma's governor, said. "I am asking all Oklahomans to stay aware of the weather and to take proper precautions to keep themselves out of harm's way."