Nation & World

70-mile-wide wave of butterflies caught on radar, confusing meteorologists

It’s a bird, it’s a plane, it’s ... butterflies?

A radar signature was initially thought by the National Weather Service in Boulder, Colo., to depict the migration of birds, according to The Denver Post.

However, later on, meteorologists determined that the signature was likely caused by a 70-mile-wide wave of migrating butterflies after they received many reports about sightings, The Associated Press said. Painted lady butterflies – sometimes mistaken for monarchs – were reported drifting with the wind, according to the AP.

“Insects rarely produce such a coherent radar signature,” the U.S. National Weather Service Denver/Boulder Colorado explained on Facebook on Wednesday. “Migrating birds do all the time.

“Migrating butterflies in high quantities explains it. Today, the butterflies are staying close to the ground.”

A painted lady butterfly flies near daisies in a garden in downtown Denver Wednesday, Oct. 4, 2017. Weather forecasters say that a lacy, cloud-like pattern drifting across a Denver-area radar screen turns out to be a 70-mile-wide wave of butterflies such as the painted ladies migrating from their summer home to their winter haunts.
A painted lady butterfly flies near daisies in a garden in downtown Denver Wednesday, Oct. 4, 2017. Weather forecasters say that a lacy, cloud-like pattern drifting across a Denver-area radar screen turns out to be a 70-mile-wide wave of butterflies such as the painted ladies migrating from their summer home to their winter haunts. David Zalubowski AP

This story was originally published October 4, 2017 at 7:25 PM with the headline "70-mile-wide wave of butterflies caught on radar, confusing meteorologists."

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