New rounds of severe thunderstorms are underway and life-threatening, potentially catastrophic, flooding risks are brewing in the central and eastern United States Tuesday, putting more than 50 million people at risk of dangerous weather this week.

After severe thunderstorms moved across Oklahoma overnight, more severe weather is expected Tuesday. Here's what we know.

Severe storms are still underway on Tuesday morning in northern Texas and Oklahoma as golf ball-sized hail has already been reported early Tuesday in Oklahoma amid numerous severe thunderstorm warnings. Meanwhile, a severe thunderstorm watch has been issued for northern Oklahoma and southern Kansas until 10 a.m. CT.