Cicada 2024 Chicago Med. In may and june 2024, illinoisans are witnessing the dual emergence of two broods of periodical cicadas at the same time, something that hasn’t happened in 221 years. These cicadas are harmless to humans and.
Most of the state of illinois will experience periodical cicada emergence in 2024, the university. For the first time in over 200 years, a “double brood” emergence of two extremely large cicada populations, brood xiii and.