HORRY COUNTY, SC (WMBF) – An odd-looking perfect circle that appeared and spread out south of Kingstree on the WMBF First Alert Weather Doppler radar Friday morning wasn't a patch of rain, but what's known as a "Roost Ring."
The "Roost Ring" shows up on radar when lots of birds all leave the nest at the same time, First Alert Meteorologist Marla Branson said. It can also happen with large amounts of bugs and bats.
The birds were likely Purple Martins leaving the nest, said Tim Armstrong with the U.S. National Weather Service in Wilmington.
Branson said she's seen the radar oddity in other places, but this is the first time she's seen it happen in our backyard.