The Latest: Storm threat shifts to Ohio Valley, southern US

The Latest on severe weather in the central and southern United States: (all times local):

9 a.m.

An unsettled weather pattern is shifting from the southern Plains into parts of the South and lower Ohio Valley, but forecasters say the storms shouldn't be as bad as originally anticipated.

The Storm Prediction Center said instability through the Mississippi Valley on Thursday won't be as great as expected. In a morning update, forecasters rolled back a relatively ominous outlook and said that while some tornadoes could occur, the likelihood of several twisters was low.

The greatest chance of severe storms is expected in an area spanning eastward from St. Louis to Indianapolis and Cincinnati and southward to Nashville, Tennessee. Other storms could occur from Ohio to the Gulf Coast.

This week's storms contributed to the deaths of three storm chasers in West Texas, two children who touched a downed power line in Fort Worth, Texas, and a truck driver whose rig was blown off a highway in El Reno, Oklahoma.


1 a.m.

The Mississippi Valley is in the severe weather bull's-eye as a storm system that already left at least six dead moved into the Dixie Alley.

The Storm Prediction Center warns that northern Mississippi and western Tennessee on Thursday will have a moderate risk of severe thunderstorms, one of the National Weather Service's most elevated risk levels.

That's as a cold front moves slowly across the Mississippi Valley, triggering thunderstorms as early as midday. The upper-level air conditions could elevate the risks of tornadoes and hailstorms.

The storm system already led to the traffic deaths of three storm chasers in West Texas and two children who touched a downed power line while playing in Fort Worth, Texas. A truck driver was killed when strong winds blew his rig off Interstate 40 in El Reno, Oklahoma.