Don't worry, all of the green and blue specks on the radar aren't Friday's looming snowstorm arriving early. These are actually thousands of migrating geese that the radar is picking up.
It happened this week on radar near Aberdeen, South Dakota, not far from the western Minnesota border.
The National Weather Service-Aberdeen explains the phenomenon like this:
Thousands of geese have started their migration north making their way into South Dakota. As these birds fly over radar sites they can often be detected. One particular radar signature sometimes termed a “roost ring” was easily seen in radar images on March 16. A “roost ring” appears as birds leave their roost and fly into the air. The ring expands until birds begin dispersing and foraging.
It's not clear that these birds on radar, but it's a good bet they're snow geese returning north after spending the winter down south.
South Dakota is known for its spectacular spring snow goose migration.
The radar loop on this page is actually really cool, almost like a small circle exploding outward.
We featured a similar story last July when radar in La Crosse, Wisconsin, picked up a massive mayfly hatch, which is part amazing and part disgusting.
According to Smithsonian, birds and bugs were first seen on radar during World War II, and they're commonly seen nowadays when birds take flight at night before landing and resting before sunrise.