The death toll from a Missouri tornado stands at 117, making it the single deadliest tornado in the United States since at least 1950.

Gov. Jay Nixon's spokesman, Sam Murphey, said Tuesday morning that the death toll is now 117.

Until this week, the single deadliest tornado on record with the National Weather Service in the past six decades was a twister that killed 116 people in Flint, Michigan in 1953.

More deaths have resulted from outbreaks of multiple tornadoes. In April, a pack of twisters roared across six Southern states, killing more than 300 people, more than two-thirds of them in Alabama. April 27 was the single deadliest day for tornadoes since 1950.

Meanwhile, the National Weather Service's Storm Prediction Center says there is a high risk of severe weather that could include tornadoes in Oklahoma, Kansas, Texas, Arkansas and Missouri.

The highest risk area for severe weather Tuesday extends from south-central Oklahoma to south-central Kansas.

The prediction center says there is a moderate risk of severe weather that could include tornadoes extending from northern Texas, across much of Oklahoma to central Kansas, and into western Arkansas and southwestern Missouri.

The severe weather could also include wind gusts of 55 to 75 mph and nearly baseball-sized hail.

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