At least 21 tornadoes were reported in parts of Texas, Oklahoma, Missouri and Arkansas from early Monday to Tuesday morning, the National Weather Service said – and more are possible, especially in parts of Missouri and Arkansas.
severe damage was immediately reported near the Tulsa airport, where a tornado was reported shortly after 6:30 am CT Tuesday. But radar indicated that it was sending debris into the air, CNN meteorologist Chad Myers said.
"That debris was … very close and moving toward" the airport, Myers said.
Severe weather is possible Tuesday in the central Plains, Missouri, Illinois, Arkansas, and parts of Texas and Louisiana
Damaging winds and hail appear to be the main threats, but more tornadoes are possible, especially in southern Missouri and northern Arkansas.
Water rescues in Oklahoma
The Tulsa area, where more than 6 inches of rain have fallen in some locations this week.
The National Weather Service in Tulsa urged people in areas to move to higher ground as more heavy rainfall is expected.
"The state-of-the-art spokeswoman of Keli Cain told CNN Tuesday morning." Multiple Oklahoma highways are closed due to high water or storm debris. Authorities warned drivers to stay off roads in anticipation of additional flooding expected overnight.  Roads in Ponca City, in northern Oklahoma, have turned into rivers, with the local government urging drivers to stay away from the water.
The police department asked residents to "get out and drive around." "On top of emergency crews trying to fix power lines and other damage from the tornado," the department said, "the roads are now flooding" due to the intense rain. "
" By trying to check out the weather you are only putting yourself and the crews in further danger. "
Stillwater Public Schools, in northern Oklahoma, announced schools in the district will be closed Tuesday "due to excessive flooding."
More flooding in the Plains and the Midwest
Due to storms have repeatedly hit the same areas recently, a serious flood threat has developed in the Plains and the Midwest
About 17 million people were flooded or flash flooded early Tuesday, including in Oklahoma City and Tulsa; Wichita, Kansas; and Kansas City and St. Louis, Missouri.
Serious river flooding – including along the already swollen Mississippi River – is also expected in the central US as another 2 to 5 inches of rain are expected to fall over the region in the next few days.