When Cicadas 2025 Illinois. Are you seeing a lot of dead cicadas? Now the great dual periodical cicada emergence of 2025 — an event of a magnitude not seen since 1803 — has burst from below to join the earlier shows in the sky.
It’s an emergence that hasn’t been seen in centuries, but the length of time depends largely on the life cycle of the cicadas. In 2025, they are expected sometime in may or early june, according to ken johnson, a horticulture educator at the university of illinois.