Tornado Emergency in Oklahoma; Latest From Joplin, Missouri

Jeff Piotrowski (storm chaser - via telephone), Sam Champion, (ABC News Weather Editor), Michelle Hare (her son Lantz is missing after tornado), Creed Jones (survived the Joplin Tornado), Tarah Castleberry (tornado survivor), CNN correspondents T.J. Holmes, Ed Lavandera and Anderson Cooper, Elizabeth Brown, Vivien Moreno, Allison Brister (Joplin High School Graduates), Rob Marciano (CNN Meteorologist) and Ford Sypher (Team Rubicon Rescuer) appear on the program to discuss the devastating tornadoes that struck various regions in America.