Weather radar doesn’t just pick up rain and snow, it can also detect other objects such as birds, insects and even flying debris. That’s what happened earlier this week in Colorado, when meteorologists picked up a large multicoloured pattern that turned out to be a 70-mile-wide swarm of butterflies!
The butterflies in question were painted ladies, which resemble monarch butterflies, although they are somewhat smaller. The bugs have descended on Colorado’s Front Range in recent weeks, feeding on flowers and sometimes flying together in what seem like clouds of butterflies!
The colors on the radar image above are a result of the butterflies’ shape and direction, not their actual colors. Radar works by sending out a beam of energy then measuring how much of that beam is reflected back and the time needed for the beam to return. If more of the beam is sent back, the object is said to have a high reflective quality, indicated by a brighter color. In recent years, birds, ants, bats, termites, mayflies, grasshoppers, and beetles have all been spotted on radar.
Image Source: US Weather Service