
KEY POINTS
- There will be 'numerous instances of flash flooding' Monday, the weather agency warned
- Nine states are currently under flood warnings, with numerous creeks and rivers being observed
- Wintry weather is expected to hit the Great Lakes early this week
The storm system that ushered in heavy rainfall over the mid-Mississippi River Valley over the weekend is expected to "progressively" move through the southeast Monday after it killed over a dozen people.