A、The effects of floods in the U.S. B、A heavy storm system struck the U.S. C、U.S. states were facing floods threats. D、Tornadoes

Last night, eight million people in 16 U.S. states were under a flood warning.
   It was what remained of a heavy storm system that struck in late December, stretching from New Mexico to Michigan and going its way east.
   It brought several powerful tornadoes to Texas, destroying homes and buildings near Dallas.
   Hailstorms, snowstorms, hundreds of flight cancellations hit the central part of the country and dozens of people died in the severe conditions brought by the system.
   For some, the worst of it came well after the storm hit, as flood waters flowed in the rivers, they covered their banks and spilled through communities.
   The Mississippi flooded parts of Illinois and its swollen water slowly spread out along the Mississippi southern part.
   It’s not expected to reach its highest point in Memphis, Tennessee, until January 9th.
1. What’s the news report mainly about?
2. What do we learn about the storm system from the news report?