The 1930s was the Dust Bowl. The 1988-89 drought, while not as severe as the Dust Bowl, was the costliest in terms of economic damage and hit most of NA. As you can see by that chart, it took five or more years to recover from it.

It's also possible to see that the region never really recovered from the 2002 drought. Droughts are getting ever more frequent and the region isn't getting enough time between them to recover.