The path length of this tornado was.04 miles.
The tornado destroyed a 1930s era home that was being used as a storage building and a barn, while it caused damage to three homes.
A second tornado was confirmed four miles north of Knoxville.
The tornado touched down at 7:55 p.m. near Perryville, Mo., and lifted at 8:57 p.m. near Christopher, Ill.
"Three homes were leveled on the west side of US 61 with dozens of other homes and structures destroyed". There was also sporadic tree damage.
The main hazards will be damaging winds and hail. The tornado was six-tenths of a mile wide and traveled 50.4 miles, the longest track of a tornado in the weather service's Paducah, Ky., coverage area in 25 years.More news: Rod Rosenstein Will Not Commit to Recusing Himself from Russia Investigation
Southern Illinois also was hit by three other tornadoes February 28 and March 1. The funnel was on the ground for almost a mile and for one minute at 7:32 p.m.
Then storms should impact the St. Louis metro area between 11 p.m. and 1 a.m.
A tornado watch remains in effect until 10 p.m.in Shawnee County.
A simulated tornado warning will be issued, and the weather radio system will be activated. Into the evening hours, there still is a chance of rain, but also a chance for severe weather.
National Weather Service says information may change in its final report.