ST. LOUIS — The National Weather Service shared radar photos on its Facebook page that seem to have captured migrating birds and insects.
The blue and green areas are believed to be Monarch butterflies heading south for the winter.
In its post, the NWS in St. Louis wrote, “A Monarch in flight would look oblate to the radar, and flapping wings would account for the changing shape! NWS St. Louis wishes good luck and a safe journey to these amazing little creatures on their long journey south!”
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