Each weekday morning, OurAmazingPlanet takes the pulse of the Earth, reporting on natural phenomena and exploration news from around the globe.
Memphis Flooding: The Mississippi River has spilled over into downtown Memphis, where authorities are going door to door to ask people to leave. [Countdown: Mightiest Floods of the Mississippi River. ]
Flood Threat Moves South: The historic Mississippi River flooding has spread all the way to the Mississippi delta. [Related: What's Behind the Record Mississippi River Flooding? ]
EF-5 Number Three: The tornado that hit Hackleburg, Ala., has been rated an EF-5 on the tornado damage scale, the highest rating and the third EF-5 from last week's outbreak. [Related: The Tornado Damage Scale In Images ]
Many Still Missing: In Alabama, dozens of people remain missing after the historic tornado outbreak that struck one week ago.
Kentucky Derby Forecast: Rain and thunderstorms could make for a muddy race at Churchill Downs on Saturday. Could it be the coldest derby ever?
Previously on Our Daily Planet: Mississippi River Flooding and Throat of Fire Eruption Photos