That phenomenon is named Brood X, or the Great Eastern Brood. It's set to return in May 2021. For the five to six weeks that they're above ground, the live cicadas — and their crunchy, discarded exoskeletons — will be impossible to miss.

Where will Brood X emerge in 2021?

The southeast corner of Pennsylvania, almost all of Maryland, parts of Delaware and New Jersey, and a few areas in New York. Ohio, almost the entire state of Indiana, a few areas in eastern Illinois, and northwest and eastern parts of Kentucky.

What month do cicadas come out 2021?

Billions of Brood X cicadas that look like this will be emerging from the ground in 15 U.S. states in May and June of 2021, and making a lot of noise.