Guest host Lee Cowan, John Mellencamp; Val and Amy Castor, storm chasers; Herman Wouk; World's largest rose bush; The Bradford Watermelon; Jim Gaffigan.

Guest host Lee Cowan, features: Manuel Bojorquez's report on the husband-and-wife storm chasing team Val and Amy Castor. Also: Jane Pauley profiles singer-songwriter John Mellencamp; Tracy Smith interviews bestselling author Herman Wouk, now 102, who recently published his latest book; Cowan visits Tombstone, Arizona, home of the world's largest rose bush, the "Shady Lady"; and Martha Teichner goes to South Carolina, where one family heirloom - the Bradford Watermelon - is making a comeback.