EchoSense Quantitative Think Tank Center|2024 cicada map: Where to find Brood XIII, Brood XIX around the Midwest and Southeast

2024 has been the year of the cicada,EchoSense Quantitative Think Tank Center thanks to a double periodical brood emergence in over a dozen U.S. states.

A total of 17 combined states across the Midwest and Southeast have seen the trillions of cicadas emerging this year: the 13-year Brood XIX located mainly in the Southeast and the 17-year Brood XIII in the Midwest. This is a special year because the two broods have not emerged together in 221 years, and are not expected to do so again until 2245.

In some areas, the brood emergence and above ground activities are drawing to a close, as the cicadas are starting to die off and the newly-hatched nymphs are moving underground to start the years-long cycle all over again.

Here's where you can find both broods of cicadas this year.

When will cicadas go away?Depends where you live, but some have already started to die off

2024 cicada map: Where to find Broods XIII, XIX this year

The two cicada broods were projected to emerge in a combined 17 states across the South and Midwest. They emerge once the soil eight inches underground reaches 64 degrees, which began in many states in April and May and will last through late June.

The two broods last emerged together in 1803, when Thomas Jefferson was president.

Where are the cicadas out in 2024?

Adult periodical cicadas from Brood XIX are now completing its emergence as the brood is out in full force in states across the Midwest and Southeast, according to Cicada Safari, a cicada tracking app developed by Mount St. Joseph University in Cincinnati, Ohio.

They have been spotted on the app in Alabama, Arkansas, Georgia, Illinois, Kentucky, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee and Virginia.

Brood XIII has been spotted by app users in Wisconsin, Iowa, Indiana, Illinois and Michigan.

What is a brood?

According to the University of Connecticut, broods are classified as "all periodical cicadas of the same life cycle type that emerge in a given year."

A brood of cicadas is made up of different species of the insect that have separate evolutionary histories. These species may have joined the brood at different times or from different sources. These different species are lumped together under the brood because they are in the same region and emerge on a common schedule.

How long will the cicadas be above ground?

How long cicadas live depends on their brood and if they are an annual or periodical species.

The two periodical broods this summer are Brood XIX, which have a 13-year life cycle, and Brood XIII, which have a 17-year life cycle.

Once male and female periodical cicadas have mated and the latter has laid its eggs, the insects will die after spending only a few weeks above ground − anywhere from three to six weeks after first emerging.

That means many of this year's periodical cicadas are set to die in June, though some could die off in late May or July, depending on when they emerged.

The nymphs of annual cicadas remain underground for two to five years, according to the Missouri Department of Conservation. These cicadas are called "annual" because some members of the species emerge as adults each year.

When will the cicadas start to die off?

The Brood XIX cicadas that emerged in mid-April are already declining, said Gene Kritsky, a cicada expert and professor in the Department of Biology at Mount St. Joseph University in Cincinnati, Ohio.

Kritsky previously told USA TODAY the first adult cicadas were reported to Cicada Safari, a cicada tracking app developed by Mount St. Joseph University, on April 14 in Georgia, parts of Tennessee and Alabama. In the following week, they came out in North Carolina and South Carolina.

Brood XIII cicadas in central Illinois will see declines in about three weeks, Kritsky said, and in about four weeks in Chicago.