In Tucson they go all summer long every year, quite loudly, in crowded choruses. In the 70s there was a local radio commercial for an air-conditioning company, that started with the quite-recognizable sound of several cicadas, starting up, rising and falling, stopping and starting again. Then the voice-over started, a very deep voice, saying:
"Nine A.M., and it's hot already."
"Gonna be a scorcher."
They let that sink in, then:
"Isn't it about time to call the air-conditioning pros at blah, blah, blah..."
A few years ago, I was riding in Tucson, and had something hit my chest. Not all that rare an occurrence, but I stopped soon after to check on something, and another rider, whom I didn't know, pulled up. We got to talking, and then you-know-what started buzzing. In my t-shirt.
I yelped, and jumped, and danced around, and finally yanked the t-shirt out of my pants and the cicada fell out at our feet. I'm pretty sure it would have looked great on Youtube.