I don't know if it qualifies as a plague of locusts because I do not know where the line is drawn, but the grasshopers were thick one year at my parents' house (which is itself surrounded by flatness and farm fields).

They were ravenous things. That ate everything. Not just "food," either, though eating a snack outside was certainly impossible and merely being outside was treacherous.

These bugs ate things like window screens, cut slivers from a vinyl swimming pool, and dined upon the siding of the house. It was really fuckin' weird even being inside of the house, since the noise of it being pelted by grasshoppers (locusts?) never really slowed down.

That was probably 25 years ago. It never happened again.

One locust is an interesting bug. Billions of locusts are an apocalyptic nightmare.