Reuters: Residents of southern states along the Mississippi River are bracing for the flooding that has swamped communities from the Ohio River Valley to eastern Oklahoma over the last week, causing thousands of evacuations and killing at least 31 people. Officials in Louisiana are checking levees daily, and Exxon Mobil Corp has decided to shut its 340,571 barrel-per-day refined products terminal in Memphis, Tennessee, as floodwaters threatened to inundate the facility just south of the city's downtown....