New rounds of severe thunderstorms 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 this week.

At least one person has died in southwest Oklahoma after flash flooding hit the region, with authorities warning people to stay off the roads as severe weather warnings continue.

Scattered thunderstorms extending across the U.S. are expected to bring severe weather to North Texas on Tuesday and Wednesday.