A fierce Christmas blizzard forced scores of US churches to cancel Christmas Day services as snow and freezing rain brought a holiday headache to millions across a huge swath of the country.

At least 23 deaths have been attributed to the storm system that blanketed the central United States beginning on Wednesday, closing several interstate highways, stranding thousands of motorists in whiteout conditions and coating roads in a glaze of ice during one of the busiest travel periods of the year.

The system, the second brutal winter blast to hit much of the United States in the past week, is not expected to clear before Saturday.

"This is a holiday mess" spanning two thirds of the country, bringing severe thunderstorms to the Gulf Coast to ice along the eastern seaboard and a raging blizzard in the Midwest and plains states, Chris Vaccaro, a spokesman for the National Weather Service (NWS) said on Friday.

"It's covering a tremendous amount of area and bringing record precipitation," he told AFP. "It's fairly unusual to have two record-setting storms in a week in mid- to late December."

The enormous system dumped 35cm of snow on Oklahoma City, an all-time record for the state.

In northern Oklahoma "a band of very heavy snow along with isolated thunder ... was producing up to four inches (10cm) of snow per hour," the weather service warned.

Up to 61 cm of snow was expected by late Christmas Day in some northern states, with blizzard warnings issued from Texas up to North Dakota on the border with Canada.

Normally balmy Dallas, Texas, was covered in 7.5cm of snow, the first time the southern city has had more than a trace of the white stuff on Christmas Day since 1926.

But while some were celebrating the wintery scene, others were ruing the cancellation of Christmas services in several states, with churches citing the treacherous conditions. Local media outlets listed hundreds of closures.

"Roads are bad," Pastor Andy Richie in Mankato, Minnesota told local KEYC-TV.

"(We) don't want you coming out if you don't think you can make it back."

The eastern US seaboard saw dangerous travel conditions on Friday, with forecasters alerting to freezing rain and heavy downpours from North Carolina up to New England.

Flood warnings were issued for parts of the northeast in anticipation of nominally rising temperatures later in the day, as snow from last weekend's storm melts.

The weather service warned of "dangerous or impossible" travel conditions in central states.

"Ice accumulations and winds will likely lead to snapped power lines and falling tree branches that add to the danger," said the forecaster.

Thousands of households were without power on Friday, including about 5,000 in the state of Iowa, the Des Moines Register reported.

In North Dakota, snowfall was forecast up to 41cm in some places, along with temperatures as low as minus 36 Celsius.

Flood and tornado warnings were issued further south with roads in the state of Alabama underwater, and freezing rain and ice storms hit the states of North Carolina, Pennsylvania, Virginia, and the Washington capital region, with more ice forecast for New England states.

South Dakota, Texas, Oklahoma and Minnesota declared states of emergency and called up national guard troops to help dig out stranded travellers.

The Kansas highway patrol reported five fatalities on the prairie state's icy roads.

Six people died on Nebraska roads, including a Christian singer on his way home from a ministry training session, the Omaha World Herald reported.

The storm was blamed for four deaths in Oklahoma, including three motorists who were struck by other vehicles after they left their own cars, the Oklahoman newspaper reported.

Three people were killed in Arizona, three in New Mexico, and one person in Minnesota, local media reported.

And along the southern US Gulf Coast, a powerful thunderstorm reportedly left one Louisiana man dead after a tree fell on his house.

Hundreds of flights were cancelled on Thursday and Friday at airports from Minneapolis to Dallas.

This is the second major weather system to sweep the country in recent days, after a record-breaking snowstorm slammed the eastern seaboard on the final busy shopping weekend before Christmas.