70-mile-wide swarm of butterflies detected by weather radar

(WSVN) - Everyone knows weather radar can pick up rain, snowstorms, tornadoes and hurricanes. Apparently it can also detect insects.

Earlier this week, the National Weather Service’s bureau in Colorado shared interactive radar images of what they said was a 70-mile-wide swarm of butterflies.

At first, meterologists thought the butterflies were a flock of birds, tweeting “radar from last hour showing what we believe to be birds.” They followed up with a comment saying “Yes! This signature is butterflies, rarely seen on our radar.”

The butterflies on the radar where painted ladies, often mistaken for monarchs, according to USA Today. The news outlet says the insects have descended on Colorado’s Front Range and are feeding on flowers.

Meteorologist Paul Schlatter says the color on the radar the butterflies’ shape and direction, not their actual color. They travel in swarms that seem like clouds.