The moths are back. The miller moth* is migrating. This particular miller is actually the cutworm moth which begins its life in wheat fields on the plains of Colorado, Nebraska, Wyoming and Kansas. Once the moth emerges, it migrates to the mountains in the west where it can feed on wildflowers. During the migration period, anywhere from 2 to 6 weeks, these fuzzy little guys (1 - 1 1/2 inches) fly at night (they have special light-sensing receptor cells in their eyes) and hide from predators during the day. They find little cracks and crevices to hide in. One of their favorite spots at my house is in the crack at the top of the door to the tack room. So... were you to be here on a morning during miller moth migration season, you would observe that I do some sort of funky dance when I open the door. That's because in my still sleeping state I forget that the moths might be there, and when they rain down on me, I jump about, flapping my hands, saying, "Ew, yuck, acchhh, bleech!"
The moths don't hurt anything, they are just big and fuzzy and startle an unsuspecting stupidly forgetful person. You will find them in just about any small crack. They will even hide in small areas in cars.
During migration season, one commonly observed phenomenon is swarms of swallows swooping and diving and flying around at intersections. They are feeding on miller moths. According to the Colorado State University Extension, this likely occurs because, "many miller moths seek shelter in automobiles and emerge while the cars are idling at stop lights. Furthermore, many moths are released as drivers open vehicle windows at intersections to let the moths escape."