Severe storms spawned over 30 tornadoes on Wednesday.
The tornadoes were reported in northern Texas, Oklahoma, Arkansas, Missouri. and Louisiana.
At least three people were killed in Oklahoma and one died in Missouri.
Several buildings were damaged.
There were more severe storms on Thursday producing large hail and damaging winds over parts of south-central/southwest Texas and the Ohio Valley, and from the mid-Mississippi Valley into the Ohio Valley.
For Friday, severe storms are expected across parts of southern and eastern Texas. A few strong/isolated severe storms are also possible across the central Appalachians vicinity.