Massive butterfly wave puzzles meteorologists

A 110-kilometer-wide blob that weather

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scientists observed this week above Denver and neighboring counties were not birds or clouds but a bunch of migrating lady butterflies, Associated Press reports. On Tuesday, the orange-and-black insects, which are now migrating south, were caught on the National Weather Service’s radar. The agency's meteorologist Paul Schlatter initially thought the cloudlike signature was produced by birds, but he soon realized, with the help of social media users, that he was actually looking at a massive wave of butterflies. 


http://www.sciencemag.org/news/2017/10/massive-butterfly-wave-puzzles-meteorologists