Twin terror in the US Midwest.

Twin terror in the US Midwest. Photo: AP

Emergency crews in tiny Pilger, Nebraska, picked through the rubble of homes and a school Tuesday, a day after a pair of tornadoes touched down almost simultaneously and killed at least two people - even as residents of northeast Nebraska and much of the Upper Midwest braced for another bout of severe weather.

"Pilger is gone," said Sanford Goshorn, director of emergency management for Stanton County. "The tornado cut right through the centre of town."

Among the dead in Pilger was a 5-year old girl, who may have been struck by debris, said the Stanton County sheriff, Mike Unger. The other reported fatality was from an automobile accident on a country road east of Pilger that was attributed to the storm.

Young tornado victim rescued.

Young tornado victim rescued. Photo: AP

Weather forecasters said residents of a section of the Midwest including Iowa, Minnesota, Nebraska and South Dakota should expect more severe weather, including the possibility of tornadoes, high winds, rain and hail.

The National Weather Service's Storm Prediction Centre in Norman, Oklahoma, reported at least one and possibly two cases in which a pair of large twisters touched down simultaneously, a rare phenomenon according to meteorologists.

While twin tornadoes are not so rare, the fact they were of similar size is unusual, said Pat Slattery, a spokesman for the National Weather Service. "Twin tornadoes happen with some frequency, but usually it is a large tornado with a smaller one accompanying it," Mr Slattery said.

Pilger in the path.

Pilger in the path. Photo: AP

Pilger, a town of about 375 people where the worst destruction was reported, is about 90 miles northwest of Omaha. Photographs showed a path of destruction that included houses that had their roofs torn off and flattened grain bins.

After Governor Dave Heineman declared a state of emergency, the Nebraska National Guard on Tuesday was aiding in the recovery work, officials said.

Sixteen other people were injured, according to officials at Faith Regional Health Services, a hospital in Norfolk, Nebraska, where most of the victims were taken.

Pilger's clean-up begins.

Pilger's clean-up begins. Photo: AP

Reduced to rubble

Pilger, about 160 km northwest of the Nebraskan capital of Omaha, had about 75 per cent of its buildings hit. Among the damaged or destroyed buildings: city hall, the fire department, post office, library and school.

Brian Reeg, who lives nearby in Winside, stood, bewildered, looking at a pile of rubble that had been St. John's Lutheran Church in Pilger.

"This is where I was baptised, where I was married and went to church my whole life," Mr Reeg said.

Mark Aken, 58, who moved to Pilger three weeks ago, said he did not have time even to unpack at the home he rented near the flattened church.

"There's a tree right through my front door," said Mr Aken, who said he is staying with family in the area for now. "My van is upside down."

An official said 40 to 50 homes were destroyed or damaged beyond repair when the tornado cut northeast through Pilger.

A threat of severe thunderstorms on Tuesday stretches from eastern Montana as far east and north as New York and Vermont, storm prediction center forecaster Bill Bunting said.

Monday's severe storms spawned preliminary reports of about two dozen tornadoes and wind and hail damage across parts of Iowa, Minnesota, Wisconsin and Illinois.

Storms damaged two dozen structures in Madison, Wisconsin and 15 to 30 houses in nearby Verona, along with an elementary school, Dane County Emergency Management said. No injuries were reported.

High winds damaged about a dozen homes in Platteville in southwest Wisconsin and several buildings on the University of Wisconsin-Platteville campus, including its stadium.

One person was seriously injured and several other people sustained minor injuries, a city spokeswoman said. 

The New York Times, Reuters