With warmer weather upon us, many birds are heading north for the summer. This is a phenomenon often picked up on weather radars.
A batch of green blips seen on a Texas radar moving north towards Forth Worth, was in fact, just that. What may have looked like rain, wind, or something else, was a flock of birds. Although It takes a very large flock, usually thousands of birds, to register on the radar, this is something that has been happening for millions of years.
These non-weather blips are also known as ground clutter. Other ground clutter often seen on weather radars include bugs, aircraft, and dust.
Bird migration video courtesy National Weather Service.