Birds can sense when bad weather is coming. If it’s going to be dangerous and they have some lead time they get out of the way. Hurricane Florence gave them plenty of time to prepare.
Weather radar shows us where it’s raining by detecting objects in the sky. When masses of birds are on the move they show up on radar, though less intense than steady rain. Flocks of birds look green on radar and are only detected when near radar stations. Since most birds migrate at night, that’s when to watch.
This radar image from 5:08am on Saturday September 15 shows the rain bands of Hurricane Florence swirling over the Carolinas. Notice that there’s no rain for miles surrounding the circle of the storm but there are intense green blobs southwest of Florence over the Florida panhandle.
Thousands of birds! They’ve heard the news and they’re leaving the area. Evacuate!
p.s. Read more about birds on radar here and an article about birds escaping storms by flying hundreds of miles out of their way