When do fireflies come out?

After months of hibernation, adult fireflies emerge on warm summer nights as darkness begins to fall. They are found in meadows, parks, gardens and woodlands of temperate and tropical climates throughout the United States and around the world.

Also known as lightning bugs, fireflies prefer humid weather and need to be near a moist area to survive. Easily identified by their signature glow, which is used to attract mates, many live long enough only to mate and lay eggs as adults. Since firefly larvae are luminescent as well, scientists theorize that the glow is also a defense mechanism that warns predators of their foul taste.