Quite a show in Chicago: Lightning struck the Willis Tower (formerly the Sears Tower, at right) on Wednesday as the storm system moved through. Scott Olson/Getty Images hide caption

itoggle caption Scott Olson/Getty Images

Friday's storm, which produced a mile-wide tornado, as it neared El Reno, Okla. Richard Rowe /Reuters /Landov hide caption

itoggle caption Richard Rowe /Reuters /Landov

After the storm: Sheet metal that was torn off a building during Friday's tornado in El Reno, Okla., ended up caught in a tree. Bill Waugh /Reuters /Landov hide caption

itoggle caption Bill Waugh /Reuters /Landov

Tuesday's weather is expected to be bad from Texas up into the nation's midsection and across to the Great Lakes. National Weather Service hide caption

itoggle caption National Weather Service

The funnel of this tornadic thunderstorm came close to the ground near South Haven, Kansas, on Sunday. Gene Blevins /Reuters /Landov hide caption

itoggle caption Gene Blevins /Reuters /Landov

Jose and Antonio Angudo were among those evacuated from Granbury, Texas, late Wednesday after a tornado devastated the area. Joyce Marshall / Fort Worth Star-Telegram /MCT / Landov hide caption

itoggle caption Joyce Marshall / Fort Worth Star-Telegram /MCT / Landov

Where is spring? Icy branches partially blocked a city street Wednesday in Sioux Falls, S.D. More wintry weather is expected there Thursday. Dirk Lammers /ASSOCIATED PRESS hide caption

itoggle caption Dirk Lammers /ASSOCIATED PRESS

While severe winter weather has caused problems for many in the Great Plains, it has also provided some opportunities for fun. On Monday, Simon Mourning (front) and Chance Cain went sliding in Wichita, Kansas. Travis Heying/Wichita Eagle /MCT /Landov hide caption

itoggle caption Travis Heying/Wichita Eagle /MCT /Landov

An ambulance is stuck in over a foot of snow off of Highway 33 West, near Belington, W.Va. on Oct. 30. Superstorm Sandy buried parts of West Virginia under more than a foot of snow. Robert Ray/AP hide caption

itoggle caption Robert Ray/AP

The Michigan Gala apples on this packing line will soon be in short supply. After a mild fall and winter, then a late-April freeze, Michigan's apple cultivation has dropped 90 percent. Noah Adams/NPR hide caption

itoggle caption Noah Adams/NPR