that is a monster tornado. reporter: battle hardened storm chasers in awe of nature s power. oh, my gosh. this is awful. dude, the trees. the trees are debarked! reporter: residents running for cover anywhere they could. in a crowded convenience store some 20 people hunkering down in a darkened commercial refrigerator. can we go in the cooler? [ screaming ] go! oh, dear heaven. god! reporter: at the same time a security camera in a nearby frozen yogurt shop catches the chaos. workers moving customers to the back and then everything goes flying. the massive tornado mowing down everything in its path. people s lives churned up and spewed out. here s the gas station that we were at. reporter: this is the convenience store now. this would have been where we walked in. reporter: all across the city, thousands and thousands of people in shock, taking the first steps on the long road to recovery. make no mistake, joplin, missouri, will rebuild, but it will