Tornadoes Touch Down with Deadly Force in New Year's Eve Tragedy

Dec. 31, 2010— -- After a week of extreme weather -- rain and mudslides in the West, blizzard conditions in the East -- it seemed the only thing missing was a tornado.

Today there were at least 20. Six people were known dead as of this evening.

From Arkansas to Missouri to Illinois, the funnel clouds came out of nowhere today in the worst outbreak of twisters on a New Year's Eve in 50 years.

In northwest Arkansas, a tornado obliterated a house and killed three people in the tiny town of Cincinnati. The violent weather then moved northeast into Missouri, killing three more before heading into Illinois.

Watch "World News with Diane Sawyer" for more on this story tonight on ABC.

In Sparta, Mo., Jessica Barnes and her three-year-old son were lucky to survive as a twister passed.

"I placed him in the tub first and then laid on top of him," Barnes said. "When we came to, he was actually on top of me and first thing he said was my house is broken. There were some boards laying on top of us, and I somehow managed to get them off of me and then screamed out for help from my neighbors."

Tornadoes are extremely rare this time of year, but those that do occur are often deadlier because they move faster in the cold air, leaving less time for warnings.

Across the country, rough weather came today like an unwelcome guest.

Blizzard warnings were in effect today for parts of Wyoming, Nebraska, Minnesota and the eastern Dakotas, according to the National Weather Service.

The central and northern Rockies and portions of the Midwest are under several winter storm watches and warnings.

On the Las Vegas strip today, people preparing to party were shivering from the cold. In Arizona, rare snow flurries dusted the desert around Phoenix, and the Denver area received about half a foot of snow overnight.

Blowing snow in North Dakota led to a massive pile-up Thursday along Interstate 94 west of Fargo. The chain reaction accident involved up to 100 cars and trucks.

In Arizona, a rare blizzard dumped a foot of snow on higher elevations and shut down Interstate 17 Thursday overnight.