Joplin tornado aftermath

Brent Long looks over a devastated Joplin, Mo. neighborhood as he helps a friend salvage belongings Monday, May 30, 2011. An EF-5 tornado tore through much of the city May 22, damaging a hospital and hundreds of homes and businesses.

President Barack Obama with residents views damage — AP Photo/J. Scott Applewhite

President Barack Obama, second from left, with residents views damage from the tornado that devastated Joplin, Mo., May 29, 2011.

Joplin residents Paula Barnett, left, and Susan Dodson console each other during a memorial service Sunday, May 29, 2011, marking the one week anniversary of an EF-5 tornado which ripped a six mile long path of destruction through Joplin, Mo.

A search and rescue team surveys the area from atop the rubble of a destroyed building in Joplin, Mo. on Saturday, May 28, 2011.

Shanie Spencer salvages what she can from what remains of her house on May 28, 2011 in Joplin, Mo.

A sign reading, "keep out God Sees You!" is seen on the wall in front of a home that was damaged when a massive tornado, May 27, 2011 in Joplin, Mo. The town continues the process of recovering from the storm.

Brandy Cossey holds a picture of her half sister that she found in the debris of her step-mothers house that was destroyed by a massive tornado on May 27, 2011 in Joplin, Missouri.

A torn American flag hangs on a pole outside of a house that was damaged during a massive tornado on May 27, 2011 in Joplin, Mo. after the EF-5 tornado ripped through the town of about 50,000 on May 22.

Tornado destruction in Joplin

The remains of an apartment building are seen after a massive tornado on May 27, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Shirley Bernings stands in what is left of her living room after the house was destroyed during a massive tornado, May 27, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Destroyed homes are seen on May 26, 2011 after a massive tornado passed through the town in Joplin, Mo.

Tornado destruction in Joplin

People take photos on May 26, 2011 in Joplin, Mo. after a massive tornado.

Tornado destruction in Joplin

Pastor John Ennis walks away after looking at a car that landed in a swimming pool — AP Photo/Charlie Riedel

Pastor John Ennis, from Columbus, Ohio, walks away after looking at a car that landed in a swimming pool and helping a resident of a devastated Joplin, Mo. neighborhood salvage items, May 26, 2011.

Tornado destruction in Joplin

A walker hangs out a window blown out by a tornado at St. John's Regional Health Center, May 26, 2011, in Joplin, Mo.

Tornado destruction in Joplin

Cars are piled by the ambulance entrance to St. John's Regional Health Center, May 26, 2011, in Joplin, Mo.

Tornado destruction in Joplin

A school bus rests among debris in a devastated Joplin, Mo. neighborhood, May 26, 2011.

Tornado destruction in Joplin

A flag files at half staff over devastated Joplin High School in Joplin, Mo., May 26, 2011.

Tornado destruction in Joplin

Lola Elbert helps look for items to salvage from her grandmother's house that was destroyed by a tornado passed through the town, May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Maggie Burlingane gathers what she can from her daughter's home on May 26, 2011 in Joplin, Missouri. The town continues the process of recovering from the storm.

Tornado destruction in Joplin

A search and rescue team member looks for victims at a devastated apartment complex in Joplin, Mo., May 26, 2011. An EF-5 tornado tore through much of the city on May 22, damaging a hospital and hundreds of homes and businesses.

Tornado destruction in Joplin

A sign is seen in front of a destroyed house indicating that it is for sale and that it includes a large sun room, May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Kyle Raley looks at a stuffed toy he found inside the home of his girlfriend after the home, May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

An American flag is seen over the rubble of homes destroyed when a tornado, May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

A sign indicates that free stuff is available inside a home that was destroyed when a massive tornado on May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Wylie Boatright, a member of the Elks Lodge #501, looks through wreckage of the lodge on May 26, 2011, in Joplin, Mo. Four people died in the building when a tornado tore through much of the city on May 22. The building in the background is the damaged St. John's Regional Health Center.

Tornado destruction in Joplin

Volunteers stop to look at debris as they walk to their work site on May 26, 2011, in Joplin, Mo.

Tornado destruction in Joplin

homes destroyed by a massive tornado — Getty Images/Joe Raedle

The rubble is seen after the homes were destroyed when a massive tornado on May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin

Bret Gibson looks at a photograph of his mother and her brothers that he found in the remains of her house after it was destroyed when a massive tornado passed through the town on May 26, 2011 in Joplin, Mo.

Tornado destruction in Joplin